BlackTreeCVE Intelligence
← Back to the CVE catalogue
Full vulnerability report · 2026
CVE-2026-76418High confidence

Cisco Secure Firewall ASA Software and Cisco Secure FTD Software Unchecked Return Value to NULL Pointer Dereference Vulnerability

Cisco · Secure Firewall ASA Software and Cisco Secure FTD Software

Official source article: Cisco CISCO-SA-ASAFTD-TUNNEL-DOS-S6MGKB75 ↗. Check the applicable product and release in the original source.

8.6HighCVSS 3.1
Recommended action
Patch only the product branches with a verified fix

CISA confirms exploitation in the wild and lists 2026-11-01 as the remediation due date. Verified remediation exists for at least one product or source, but 1,529 structured product or package states remain unresolved. Apply remediation only to the exact product branch confirmed by its source.

Fix availability varies by product
R
Operational reassessment

Published severity in operational context

Open reassessment dashboard →
Published severityHighOperational priority:Critical, raised one band.upgradedsince 29 Oct 2026

Evidence used

  • CISA confirms exploitation in the wild.
  • The selected CVSS metric records a network-reachable, unauthenticated path with no user interaction.
  • EPSS is 0.82% for the current model date.

Compensating controls

  • Validate the affected product branch and deploy the verified fixed release.
  • Restrict the affected network interface to trusted sources where business-safe.
  • Increase monitoring for the attack path and post-exploitation behaviour described in the report.

Verification

  1. Confirm that the asset runs Cisco Secure Firewall ASA Software and Cisco Secure FTD Software and falls inside the recorded affected range.
  2. Verify the installed build against the product-specific fixed version after deployment.
  3. Validate exposure, authentication requirements and compensating controls in the actual environment.
  4. Reopen this reassessment when CVSS, KEV, EPSS, exploit evidence or remediation changes.
Mitigation target: Within 3 daysRemediation target: Within 90 days

This automated reassessment organises public evidence. It does not know asset exposure, business impact or control effectiveness and does not replace CVSS or a human risk decision.

Cross-source reconciliation

Remediation availability differs by product scope

Verified remediation exists for at least one product or source, but 1,529 structured product or package states remain unresolved. Apply remediation only to the exact product branch confirmed by its source.

Direct vendor intelligence

Authoritative vendor CSAF and VEX advisories

Structured product status and remediation from the issuing vendor. Product-state explanations are always visible; large lists can be searched or downloaded.

1 current
cisco-sa-asaftd-tunnel-dos-s6mgkb75 · CSAF 2.0 · revision 1.0.0 · finalCisco PSIRTCisco Secure Firewall Adaptive Security Appliance and Secure Firewall Threat Defense Software Remote Access SSL VPN Tunnel Denial of Service Vulnerability
1,529 known affected

The vendor explicitly identifies these products as affected by this CVE.

  • Cisco Secure Firewall Adaptive Security Appliance (ASA) Software 9.16.1 when installed on Cisco Firepower 2100 Series
  • Cisco Secure Firewall Adaptive Security Appliance (ASA) Software 9.16.1 when installed on Cisco Firepower 1000 Series
  • Cisco Secure Firewall Adaptive Security Appliance (ASA) Software 9.16.1 when installed on Cisco ASA 5500-X Series Firewalls
  • Cisco Secure Firewall Adaptive Security Appliance (ASA) Software 9.16.1 when installed on Cisco 3000 Series Industrial Security Appliances (ISA)
  • Cisco Secure Firewall Adaptive Security Appliance (ASA) Software 9.16.1 when installed on Cisco Firepower 9000 Series
  • Cisco Secure Firewall Adaptive Security Appliance (ASA) Software 9.16.1 when installed on Cisco Firepower 4100 Series
  • Cisco Secure Firewall Adaptive Security Appliance (ASA) Software 9.16.1 when installed on Cisco Adaptive Security Virtual Appliance (ASAv)
  • Cisco Secure Firewall Adaptive Security Appliance (ASA) Software 9.16.1.28 when installed on Cisco Firepower 2100 Series
  • Cisco Secure Firewall Adaptive Security Appliance (ASA) Software 9.16.1.28 when installed on Cisco Firepower 1000 Series
  • Cisco Secure Firewall Adaptive Security Appliance (ASA) Software 9.16.1.28 when installed on Cisco ASA 5500-X Series Firewalls
  • Cisco Secure Firewall Adaptive Security Appliance (ASA) Software 9.16.1.28 when installed on Cisco 3000 Series Industrial Security Appliances (ISA)
  • Cisco Secure Firewall Adaptive Security Appliance (ASA) Software 9.16.1.28 when installed on Cisco Firepower 9000 Series
Summary
Complete.
Remediation
Cisco has released software updates that address this vulnerability.
Optional official sources

National CERT insights
?CERT means Computer Emergency Response Team; CSIRT is the closely related term Computer Security Incident Response Team.

Choose official national sources for this report. Each advisory shows its original language. Your selection is remembered on this device and included in shared links.

Official European source

ENISA European Vulnerability Database

Official EUVD identifiers, advisory evidence and known-exploited context. Missing fields are not treated as evidence of low risk.

1 current
ENISA EUVD identifier

EUVD-2026-112462

CISA KEV mirrored by ENISA

A vulnerability in the Remote Access SSL VPN service of Cisco Secure Firewall Adaptive Security Appliance (ASA) Software and Cisco Secure Firewall Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause the device to reload unexpectedly, resulting in a denial of service (DoS) condition. This vulnerability is due to logic errors when secondary authentication is configured on a tunnel group. An attacker could exploit this vulnerability by sending a crafted request when connecting to the SSL remote access VPN. A successful exploit could allow the attacker to cause the affected device to reload, resulting in a DoS condition.

EUVD state
Present in the current official mapping
Known exploitation
Recorded by ENISA since 29 Oct 2026. Evidence sources: cisa_kev.
ENISA score
8.6 · CVSS 3.1
Advisory evidence
1 linked advisory record
Recommended actionPatch only the product branches with a verified fix

CISA confirms exploitation in the wild and lists 2026-11-01 as the remediation due date. Verified remediation exists for at least one product or source, but 1,529 structured product or package states remain unresolved. Apply remediation only to the exact product branch confirmed by its source.

Fix availability varies by product
01

What, why and how

Cisco Secure Firewall ASA Software and Cisco Secure FTD Software contains an unchecked return value to NULL pointer dereference vulnerability that could allow an unauthenticated, remote attacker to cause the device to reload unexpectedly, resulting in a denial of service (DoS) condition.

What

Cisco Secure Firewall ASA Software and Cisco Secure FTD Software contains an unchecked return value to NULL pointer dereference vulnerability that could allow an unauthenticated, remote attacker to cause the device to reload unexpectedly, resulting in a denial of service (DoS) condition.

Why

The product does not check for an error after calling a function that can return with a NULL pointer if the function fails, which leads to a resultant NULL pointer dereference.

How

An attacker operating through a network path may attempt exploitation without authentication or user interaction. If successful, the issue may disrupt the affected service.

What

Cisco Secure Firewall ASA Software and Cisco Secure FTD Software contains an unchecked return value to NULL pointer dereference vulnerability that could allow an unauthenticated, remote attacker to cause the device to reload unexpectedly, resulting in a denial of service (DoS) condition.

Why

The product does not check for an error after calling a function that can return with a NULL pointer if the function fails, which leads to a resultant NULL pointer dereference.

How

An attacker operating through a network path may attempt exploitation without authentication or user interaction. If successful, the issue may disrupt the affected service.

02

Exploit reality and attack path

CVSS severity, EPSS forecast probability, public exploit material and CISA-confirmed exploitation are separate signals.

Observed exploitation
?Confirmed exploitation and public exploit material are separate signals. Attacks can occur without public proof-of-concept or exploit code.
Confirmed in the wild

CISA added this CVE to its Known Exploited Vulnerabilities catalogue on 2026-10-29.

Public PoC / exploit material
?Confirmed exploitation and public exploit material are separate signals. Attacks can occur without public proof-of-concept or exploit code.
None recorded

No exploit-tagged reference or CISA SSVC proof-of-concept state is currently recorded. Research may still exist outside the structured feeds.

Likely attack path
a network path → Unchecked Return Value to NULL Pointer Dereference → disrupt the affected service
Attack surface
Network
Privileges required
None: unauthenticated exploitation is possible
User interaction
None
Attack complexity
Low: no specialised conditions are recorded
Security boundary
Changed: exploitation can affect a different security authority
Weakness
?CWE means Common Weakness Enumeration: a standard category for the underlying weakness.
CWE-690 ↗

CWE-690: Unchecked Return Value to NULL Pointer Dereference. The product does not check for an error after calling a function that can return with a NULL pointer if the function fails, which leads to a resultant NULL pointer dereference.

CVSS vector
?CVSS means Common Vulnerability Scoring System. The vector records the metric values used to calculate technical severity.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H

Common Vulnerability Scoring System 3.1: the compact vector below is decoded into plain language.

AVNetworkAttack vector: The vulnerable component can be reached over a network.ACLowAttack complexity: No specialised conditions are required beyond attacker-controlled input.PRNonePrivileges required: The attacker does not need an account or existing privileges.UINoneUser interaction: No action by another user is required.SChangedScope: The attack can affect a component governed by a different security authority.CNoneConfidentiality impact: No direct loss is represented by this metric.INoneIntegrity impact: No direct loss is represented by this metric.AHighAvailability impact: A successful attack can cause a major loss.
Post-exploitation / living off the land
No specific living-off-the-land technique is confirmed in the structured sources. Monitor normal administration tools for activity inconsistent with the affected service's baseline.
NetworkUnauthenticatedDenial of serviceCWE-690CISA KEV
A

Official authority intelligence

Only matched European and national findings are included. Language selectors and unavailable sources are omitted.

ENISA EUVD · EUVD-2026-112462Known-exploited evidence recorded

A vulnerability in the Remote Access SSL VPN service of Cisco Secure Firewall Adaptive Security Appliance (ASA) Software and Cisco Secure Firewall Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause the device to reload unexpectedly, resulting in a denial of service (DoS) condition. This vulnerability is due to logic errors when secondary authentication is configured on a tunnel group. An attacker could exploit this vulnerability by sending a crafted request when connecting to the SSL remote access VPN. A successful exploit could allow the attacker to cause the affected device to reload, resulting in a DoS condition.

Official EUVD record ↗
BSI · German · WID-SEC-2026-4238Cisco Secure Firewall Threat Defense und Cisco ASA: Schwachstelle ermöglicht Denial of Service

Ein entfernter, anonymer Angreifer kann eine Schwachstelle in Cisco Secure Firewall Threat Defense und Cisco ASA (Adaptive Security Appliance) ausnutzen, um einen Denial of Service Angriff durchzuführen.

Official advisory ↗
Canadian Centre for Cyber Security · English · AV26-1102Cisco security advisory (AV26-1102) - Update 1

As of October 28, 2026, Cisco is affected by a vulnerability in the following products: Cisco indicates that CVE-2026-76418 is exploited in the wild.

Official advisory ↗
Cyber Security Agency of Singapore · English · CSA-SB-20261104Security Bulletin 04 Nov 2026

The Cyber Security Agency of Singapore included this CVE in its official Security Bulletin 04 Nov 2026, published on 4 November 2026. Open the linked bulletin for the product, severity and reference information published in that issue.

Official advisory ↗
INCIBE-CERT · Spanish · multiples-vulnerabilidades-en-productos-de-cisco-20Múltiples vulnerabilidades en productos de Cisco

Eric Fernald ha informado sobre una vulnerabilidad en ASA y FTD. Junto con las incidencias de Node.js comunicadas por Khai Tran y Sylvie Mayer, de OpenAI Codex Security, Hasan Flayyih Abdullah y anagnorisis2peripeteia, se reúnen 5 vulnerabilidades: 1 de severidad crítica y 4 altas. Su explotación podría permitir ejecutar código, divulgar información, eludir comprobaciones de seguridad o provocar denegaciones de servicio.

Official advisory ↗
INCIBE-CERT · Spanish · actualizacion-30102026-multiples-vulnerabilidades-en-productos-de-cisco[Actualización 30/10/2026] Múltiples vulnerabilidades en productos de Cisco

Eric Fernald ha informado sobre una vulnerabilidad en ASA y FTD. Junto con las incidencias de Node.js comunicadas por Khai Tran y Sylvie Mayer, de OpenAI Codex Security, Hasan Flayyih Abdullah y anagnorisis2peripeteia, se reúnen 5 vulnerabilidades: 1 de severidad crítica y 4 altas. Su explotación podría permitir ejecutar código, divulgar información, eludir comprobaciones de seguridad o provocar denegaciones de servicio.

Official advisory ↗
CERT-FR · French · CERTFR-2026-AVI-1412Avis du CERT-FR

Une vulnérabilité a été découverte dans les produits Cisco. Elle permet à un attaquant de provoquer un déni de service à distance. Cisco indique que la vulnérabilité CVE-2026-76418 est activement exploitée.

Official advisory ↗
NBSZ-NKI · Hungarian · cve-2026-76418CVE-2026-76418

A termék nem ellenőrzi a hibát egy olyan függvény meghívását követően, amely sikertelen végrehajtás esetén NULL-mutatóval térhet vissza, ez pedig NULL-mutató dereferálásához vezethet.

Official advisory ↗
CSIRT Italia · Italian · cisco-rilevato-sfruttamento-in-rete-della-cve-2026-76418Cisco: rilevato sfruttamento in rete della CVE-2026-76418

Rilevato lo sfruttamento attivo in rete della CVE-2026-76418 - di tipo "Denial of Service" e con score CVSS v3.1 pari a 8.6 - che interessa i prodotti Cisco Secure Firewall Adaptive Security Appliance (ASA) e Cisco Secure Firewall Threat Defense (FTD). La vulnerabilità è dovuta a errori logici nella gestione dell'autenticazione secondaria quando questa è configurata nei tunnel group del servizio Remote Access SSL VPN. Un attaccante remoto non autenticato, tramite l'invio di richieste opportunamente predisposte verso il servizio SSL VPN, potrebbe causare il riavvio inatteso del dispositivo target.

Official advisory ↗
KISA KrCERT/CC · Korean · KNVD-7029Cisco 제품 보안 업데이트 권고

Cisco Secure Firewall Adaptive Security Appliance(ASA), Secure Firewall Threat Defense(FTD)에서 발생하는 Unchecked Return Value to NULL Pointer Dereference 취약점(CVE-2026-76418) [1][2]

Official advisory ↗
KISA KrCERT/CC · Korean · KNVD-7027美 CISA 발표 주요 Exploit 정보공유(Update. 2026-10-29)

Cisco Secure Firewall ASA Software and Cisco Secure FTD Software Unchecked Return Value to NULL Pointer Dereference Vulnerability

Official advisory ↗
NCSC-NL · Dutch · NCSC-2026-0463Kwetsbaarheid verholpen in Cisco Secure Firewall ASA en FTD Software

Cisco bevestigt dat de kwetsbaarheid actief wordt misbruikt. Deze kwetsbaarheid met kenmerk CVE-2026-76418 heeft een CVSS-score van 8.6 en bevindt zich in de Remote Access SSL VPN-functionaliteit. Een niet-geauthenticeerde kwaadwillende kan de kwetsbaarheid op afstand misbruiken door een speciaal vervaardigd verzoek naar de VPN-dienst te versturen. Hierdoor kan het getroffen apparaat onverwacht herstarten, wat kan leiden tot een Denial-of-Service (DoS) en verstoring van de dienstverlening. Voor succesvol misbruik moet de SSL VPN-dienst bereikbaar zijn en secundaire authenticatie zijn geconfigureerd voor een VPN-tunnelgroep. Een succesvolle VPN-aanmelding is niet vereist.

Official advisory ↗
03

Patch and workaround

Operational remediation based on structured source evidence.

Status
?Patch availability is based on structured fixed-version fields and authoritative update references. If no fix is verified, check the vendor advisory before making a change.
Fix availability varies by product
Affected
Fixed
No fixed version is explicitly recorded in the structured CVE data.
Action
Use the product-specific evidence above. Patch only products with a verified fixed release, and keep every affected or under-investigation state without a matching fix in the remediation queue.
Workaround
No verified workaround is recorded. If business-safe, reduce exposure to the affected interface and allow only trusted sources until authoritative guidance is available.
Official vendor articles1 stored document

Linked articles are downloaded and versioned as source evidence. A CVE mention or approved update relationship does not, by itself, verify a fix for every product branch.

04

Evidence and provenance

Published 28 Oct 2026 · Last source change 30 Oct 2026, 03:55 UTC · CWE-690 · Unchecked Return Value to NULL Pointer Dereference

CVE recordCVE.org · 5.2
CVSS sourceCNA
EPSS source
?The date BlackTree first stored a score for this CVE from the daily FIRST EPSS feed.
FIRST · tracked since 2026-10-29
European sourceENISA EUVD · EUVD-2026-112462
Product sourceVendor CSAF · Cisco PSIRT
Remediation sourceVendor CSAF · Cisco PSIRT
CWE sourceCNA
NVD statusNVD enriched

Core structured fields are present and their contributing authorities are shown above.

Material change intelligence

What changed after publication

View recent updates ↗
  1. BlackTree coverageBlackTree article coverage changed from no BlackTree article to 1 BlackTree article.
    Before
    no BlackTree article
    After
    1 BlackTree article
    BlackTree editorial ↗
  2. ENISA known-exploited stateENISA EUVD now records this CVE in its known-exploited dataset.
    Before
    not listed in ENISA EUVD known-exploited dataset
    After
    listed in ENISA EUVD known-exploited dataset (EUVD-2026-112462)
    ENISA EUVD ↗
  3. Vendor guidanceAuthoritative vendor guidance changed: added vendor advisory: sec.cloudapps.cisco.com/cisco-sa-asaftd-tunnel-dos-s6mgkb75; removed patch: sec.cloudapps.cisco.com/cisco-sa-asaftd-tunnel-dos-s6mgkb75; removed remediation: sec.cloudapps.cisco.com/cisco-sa-asaftd-tunnel-dos-s6mgkb75.
    Before
    patch: sec.cloudapps.cisco.com/cisco-sa-asaftd-tunnel-dos-s6mgkb75 · remediation: sec.cloudapps.cisco.com/cisco-sa-asaftd-tunnel-dos-s6mgkb75
    After
    vendor advisory: sec.cloudapps.cisco.com/cisco-sa-asaftd-tunnel-dos-s6mgkb75
    psirt@cisco.com ↗
  4. Remediation statusRemediation status changed from Mitigation available to Awaiting fix.
    Before
    Mitigation available
    After
    Awaiting fix
    psirt@cisco.com ↗
  5. Vendor guidanceAuthoritative vendor guidance changed: added vendor advisory: sec.cloudapps.cisco.com/cisco-sa-asaftd-tunnel-dos-s6mgkb75.
    Before
    no authoritative guidance recorded
    After
    vendor advisory: sec.cloudapps.cisco.com/cisco-sa-asaftd-tunnel-dos-s6mgkb75
    psirt@cisco.com ↗
  6. Vendor guidanceAuthoritative vendor guidance changed: removed patch: sec.cloudapps.cisco.com/cisco-sa-asaftd-tunnel-dos-s6mgkb75; removed remediation: sec.cloudapps.cisco.com/cisco-sa-asaftd-tunnel-dos-s6mgkb75.
    Before
    patch: sec.cloudapps.cisco.com/cisco-sa-asaftd-tunnel-dos-s6mgkb75 · remediation: sec.cloudapps.cisco.com/cisco-sa-asaftd-tunnel-dos-s6mgkb75
    After
    no authoritative guidance recorded
    CISA KEV ↗
  7. Remediation statusRemediation status changed from Mitigation available to Awaiting fix.
    Before
    Mitigation available
    After
    Awaiting fix
    CISA KEV ↗
  8. Vendor guidanceAuthoritative vendor guidance changed: removed patch: sec.cloudapps.cisco.com/cisco-sa-asaftd-tunnel-dos-s6mgkb75; removed remediation: sec.cloudapps.cisco.com/cisco-sa-asaftd-tunnel-dos-s6mgkb75.
    Before
    patch: sec.cloudapps.cisco.com/cisco-sa-asaftd-tunnel-dos-s6mgkb75 · remediation: sec.cloudapps.cisco.com/cisco-sa-asaftd-tunnel-dos-s6mgkb75
    After
    no authoritative guidance recorded
    CISA KEV ↗
  9. Remediation statusRemediation status changed from Mitigation available to Awaiting fix.
    Before
    Mitigation available
    After
    Awaiting fix
    CISA KEV ↗
  10. ENISA EUVD mappingEUVD-2026-112462 was added to the official ENISA EUVD mapping for this CVE.
    Before
    not recorded
    After
    {"euvdId":"EUVD-2026-112462"}
    ENISA EUVD ↗
  11. Vendor guidanceAuthoritative vendor guidance changed: removed patch: sec.cloudapps.cisco.com/cisco-sa-asaftd-tunnel-dos-s6mgkb75; removed remediation: sec.cloudapps.cisco.com/cisco-sa-asaftd-tunnel-dos-s6mgkb75.
    Before
    patch: sec.cloudapps.cisco.com/cisco-sa-asaftd-tunnel-dos-s6mgkb75 · remediation: sec.cloudapps.cisco.com/cisco-sa-asaftd-tunnel-dos-s6mgkb75
    After
    no authoritative guidance recorded
    CISA KEV ↗
  12. Remediation statusRemediation status changed from Mitigation available to Awaiting fix.
    Before
    Mitigation available
    After
    Awaiting fix
    CISA KEV ↗
  13. CISA KEV stateCISA KEV now confirms exploitation in the wild.
    Before
    not listed in CISA KEV
    After
    listed in CISA KEV since 2026-10-29
    CISA KEV ↗
  14. Vendor guidanceAuthoritative vendor guidance changed: removed patch: sec.cloudapps.cisco.com/cisco-sa-asaftd-tunnel-dos-s6mgkb75; removed remediation: sec.cloudapps.cisco.com/cisco-sa-asaftd-tunnel-dos-s6mgkb75.
    Before
    patch: sec.cloudapps.cisco.com/cisco-sa-asaftd-tunnel-dos-s6mgkb75 · remediation: sec.cloudapps.cisco.com/cisco-sa-asaftd-tunnel-dos-s6mgkb75
    After
    no authoritative guidance recorded
    CNA ↗
  15. Remediation statusRemediation status changed from Mitigation available to Awaiting fix.
    Before
    Mitigation available
    After
    Awaiting fix
    CNA ↗
  16. Catalogue recordCVE added to the BlackTree catalogue.
    CNA ↗
  17. Affected versionsThe structured affected or fixed version information changed.
    Before
    Cisco Secure Firewall Adaptive Security Appliance (ASA) Software 9.16.1 when installed on Cisco Firepower 2100 Series; Cisco Secure Firewall Adaptive Security Appliance (ASA) Software 9.16.1 when installed on Cisco Firepower 1000 Series; Cisco Secure Firewall Adaptive Security Appliance (ASA) Software 9.16.1 when installed on Cisco ASA 5500-X Series Firewalls; Cisco Secure Firewall Adaptive Security Appliance (ASA) Software 9.16.1 when installed on Cisco 3000 Series Industrial Security Appliances (ISA); Cisco Secure Firewall Adaptive Security Appliance (ASA) Software 9.16.1 when installed on Cisco Firepower 9000 Series; Cisco Secure Firewall Adaptive Security Appliance (ASA) Software 9.16.1 when installed on Cisco Firepower 4100 Series; Cisco Secure Firewall Adaptive Security Appliance (ASA) Software 9.16.1 when installed on Cisco Adaptive Security Virtual Appliance (ASAv); Cisco Secure Firewall Adaptive Security Appliance (ASA) Software 9.16.1.28 when installed on Cisco Firepower 2100 Series; Cisco Secure Firewall Adaptive Security Appliance (ASA) Software 9.16.1.28 when installed on Cisco Firepower 1000 Series; Cisco Secure Firewall Adaptive Security Appliance (ASA) Software 9.16.1.28 when installed on Cisco ASA 5500-X Series Firewalls; Cisco Secure Firewall Adaptive Security Appliance (ASA) Software 9.16.1.28 when installed on Cisco 3000 Series Industrial Security Appliances (ISA); Cisco Secure Firewall Adaptive Security Appliance (ASA) Software 9.16.1.28 when installed on Cisco Firepower 9000 Series; Cisco Secure Firewall Adaptive Security Appliance (ASA) Software 9.16.1.28 when installed on Cisco Firepower 4100 Series; Cisco Secure Firewall Adaptive Security Appliance (ASA) Software 9.16.1.28 when installed on Cisco Adaptive Security Virtual Appliance (ASAv); Cisco Secure Firewall Adaptive Security Appliance (ASA) Software 9.16.2 when installed on Cisco Firepower 2100 Series; Cisco Secure Firewall Adaptive Security Appliance (ASA) Software 9.16.2 when installed on Cisco Firepower 1000 Series; Cisco Secure Firewall Adaptive Security Appliance (ASA) Software 9.16.2 when installed on Cisco ASA 5500-X Series Firewalls; Cisco Secure Firewall Adaptive Security Appliance (ASA) Software 9.16.2 when installed on Cisco 3000 Series Industrial Security Appliances (ISA); Cisco Secure Firewall Adaptive Security Appliance (ASA) Software 9.16.2 when installed on Cisco Firepower 9000 Series; Cisco Secure Firewall Adaptive Security Appliance (ASA) Software 9.16.2 when installed on Cisco Firepower 4100 Series; Cisco Secure Firewall Adaptive Security Appliance (ASA) Software 9.16.2 when installed on Cisco Adaptive Security Virtual Appliance (ASAv); Cisco Secure Firewall Adaptive Security Appliance (ASA) Software 9.16.2.3 when installed on Cisco Firepower 2100 Series; Cisco Secure Firewall Adaptive Security Appliance (ASA) Software 9.16.2.3 when installed on Cisco Firepower 1000 Series; Cisco Secure Firewall Adaptive Security Appliance (ASA) Software 9.16.2.3 when installed on Cisco ASA 5500-X Series Firewalls; Cisco Secure Firewall Adaptive Security Appliance (ASA) Software 9.16.2.3 when installed on Cisco 3000 Series Industrial Security Appliances (ISA); Cisco Secure Firewall Adaptive Security Appliance (ASA) Software 9.16.2.3 when installed on Cisco Firepower 9000 Series; Cisco Secure Firewall Adaptive Security Appliance (ASA) Software 9.16.2.3 when installed on Cisco Firepower 4100 Series; Cisco Secure Firewall Adaptive Security Appliance (ASA) Software 9.16.2.3 when installed on Cisco Adaptive Security Virtual Appliance (ASAv); Cisco Secure Firewall Adaptive Security Appliance (ASA) Software 9.16.2.7 when installed on Cisco Firepower 2100 Series; Cisco Secure Firewall Adaptive Security Appliance (ASA) Software 9.16.2.7 when installed on Cisco Firepower 1000 Series; and 1492 more
    After
    Cisco Secure Firewall Adaptive Security Appliance (ASA) Software 9.16.1 when installed on Cisco Firepower 2100 Series; Cisco Secure Firewall Adaptive Security Appliance (ASA) Software 9.16.1 when installed on Cisco Firepower 1000 Series; Cisco Secure Firewall Adaptive Security Appliance (ASA) Software 9.16.1 when installed on Cisco ASA 5500-X Series Firewalls; Cisco Secure Firewall Adaptive Security Appliance (ASA) Software 9.16.1 when installed on Cisco 3000 Series Industrial Security Appliances (ISA); Cisco Secure Firewall Adaptive Security Appliance (ASA) Software 9.16.1 when installed on Cisco Firepower 9000 Series; Cisco Secure Firewall Adaptive Security Appliance (ASA) Software 9.16.1 when installed on Cisco Firepower 4100 Series; Cisco Secure Firewall Adaptive Security Appliance (ASA) Software 9.16.1 when installed on Cisco Adaptive Security Virtual Appliance (ASAv); Cisco Secure Firewall Adaptive Security Appliance (ASA) Software 9.16.1.28 when installed on Cisco Firepower 2100 Series; Cisco Secure Firewall Adaptive Security Appliance (ASA) Software 9.16.1.28 when installed on Cisco Firepower 1000 Series; Cisco Secure Firewall Adaptive Security Appliance (ASA) Software 9.16.1.28 when installed on Cisco ASA 5500-X Series Firewalls; Cisco Secure Firewall Adaptive Security Appliance (ASA) Software 9.16.1.28 when installed on Cisco 3000 Series Industrial Security Appliances (ISA); Cisco Secure Firewall Adaptive Security Appliance (ASA) Software 9.16.1.28 when installed on Cisco Firepower 9000 Series; Cisco Secure Firewall Adaptive Security Appliance (ASA) Software 9.16.1.28 when installed on Cisco Firepower 4100 Series; Cisco Secure Firewall Adaptive Security Appliance (ASA) Software 9.16.1.28 when installed on Cisco Adaptive Security Virtual Appliance (ASAv); Cisco Secure Firewall Adaptive Security Appliance (ASA) Software 9.16.2 when installed on Cisco Firepower 2100 Series; Cisco Secure Firewall Adaptive Security Appliance (ASA) Software 9.16.2 when installed on Cisco Firepower 1000 Series; Cisco Secure Firewall Adaptive Security Appliance (ASA) Software 9.16.2 when installed on Cisco ASA 5500-X Series Firewalls; Cisco Secure Firewall Adaptive Security Appliance (ASA) Software 9.16.2 when installed on Cisco 3000 Series Industrial Security Appliances (ISA); Cisco Secure Firewall Adaptive Security Appliance (ASA) Software 9.16.2 when installed on Cisco Firepower 9000 Series; Cisco Secure Firewall Adaptive Security Appliance (ASA) Software 9.16.2 when installed on Cisco Firepower 4100 Series; Cisco Secure Firewall Adaptive Security Appliance (ASA) Software 9.16.2 when installed on Cisco Adaptive Security Virtual Appliance (ASAv); Cisco Secure Firewall Adaptive Security Appliance (ASA) Software 9.16.2.3 when installed on Cisco Firepower 2100 Series; Cisco Secure Firewall Adaptive Security Appliance (ASA) Software 9.16.2.3 when installed on Cisco Firepower 1000 Series; Cisco Secure Firewall Adaptive Security Appliance (ASA) Software 9.16.2.3 when installed on Cisco ASA 5500-X Series Firewalls; Cisco Secure Firewall Adaptive Security Appliance (ASA) Software 9.16.2.3 when installed on Cisco 3000 Series Industrial Security Appliances (ISA); Cisco Secure Firewall Adaptive Security Appliance (ASA) Software 9.16.2.3 when installed on Cisco Firepower 9000 Series; Cisco Secure Firewall Adaptive Security Appliance (ASA) Software 9.16.2.3 when installed on Cisco Firepower 4100 Series; Cisco Secure Firewall Adaptive Security Appliance (ASA) Software 9.16.2.3 when installed on Cisco Adaptive Security Virtual Appliance (ASAv); Cisco Secure Firewall Adaptive Security Appliance (ASA) Software 9.16.2.7 when installed on Cisco Firepower 2100 Series; Cisco Secure Firewall Adaptive Security Appliance (ASA) Software 9.16.2.7 when installed on Cisco Firepower 1000 Series; and 1499 more
    Cisco PSIRT ↗
  18. Remediation statusRemediation status changed from Awaiting fix to Mitigation available.
    Before
    Awaiting fix
    After
    Mitigation available
    Cisco PSIRT ↗
Material fields only · duplicate refreshes suppressed · history retained for the configured operational retention period
CVE published
Added to CISA KEV
ENISA EUVD · EUVD-2026-112462↗CVE authority or vendor reference · Cisco CISCO-SA-ASAFTD-TUNNEL-DOS-S6MGKB75↗CISA KEV record↗Official CVE record (CNA and ADP data)↗NVD record↗
Technical terms and abbreviations used in this report
CVE
Common Vulnerabilities and Exposures: the public identifier for one disclosed vulnerability.
CVSS
Common Vulnerability Scoring System: a technical severity framework; it is not patching priority by itself.
EPSS
Exploit Prediction Scoring System: FIRST's estimate of the probability that exploitation activity will be observed in the next 30 days; it is a forecast, not confirmation.
CWE
Common Weakness Enumeration: the standard category describing the underlying software or hardware weakness.
CNA
CVE Numbering Authority: an organisation authorised to assign and publish CVE records.
CISA ADP
Cybersecurity and Infrastructure Security Agency Authorized Data Publisher: structured enrichment added to a CVE record.
NVD
National Vulnerability Database: NIST's enrichment service for CVE records.
CERT / CSIRT
A computer security incident response team that publishes warnings or coordinates incident response.
PoC
Proof of concept: public material that demonstrates or helps reproduce exploitation.
CSAF
Common Security Advisory Framework: a machine-readable format for security advisories.
LoTL
Living off the land: abuse of legitimate tools or system functions during an attack.
Free version - for non-commercial use only.CVE-2026-76418 · cve.blacktree.nl