CVE-2026-20079: Cisco Firewall Management Center Authentication Bypass Using an Alternate Path or Channel Vulnerability

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CISA confirms exploitation in the wild and lists 2026-09-12 as the remediation due date.

Fix not verified

What, why and how

Cisco Secure Firewall Management Center (FMC) Software and Cisco Security Cloud Control (SCC) Firewall Management contain an authentication Bypass using an alternate path or channel vulnerability that could allow an unauthenticated, remote attacker to bypass authentication and execute script files on an affected device to obtain root access to the underlying operating system.

What

Why

The product requires authentication, but the product has an alternate path or channel that does not require authentication.

How

An attacker operating through a network path may attempt exploitation without authentication or user interaction. If successful, the issue may bypass an access boundary or take over an account.

What

Why

The product requires authentication, but the product has an alternate path or channel that does not require authentication.

How

An attacker operating through a network path may attempt exploitation without authentication or user interaction. If successful, the issue may bypass an access boundary or take over an account.

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 2026-09-09.

Public PoC / exploit material

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

Reference recorded

A structured CVE source labels at least one public reference as exploit material. BlackTree has not independently validated that it is safe, reliable or weaponised.

Likely attack path: a network path → Authentication Bypass Using an Alternate Path or Channel → bypass an access boundary or take over an account
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-288 ↗
CWE-288: Authentication Bypass Using an Alternate Path or Channel. The product requires authentication, but the product has an alternate path or channel that does not require authentication.
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:H/I:H/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.CHighConfidentiality impact: A successful attack can cause a major loss.IHighIntegrity impact: A successful attack can cause a major loss.AHighAvailability impact: A successful attack can cause a major loss.
Post-exploitation / living off the land: Stolen credentials, tokens and legitimate administration functions may provide continued access without deploying a large custom toolset.

NetworkUnauthenticatedCWE-288CISA KEVPublic exploit reference

Official authority intelligence

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

ENISA EUVD · EUVD-2026-9438Known-exploited evidence recorded

A vulnerability in the web interface of Cisco Secure Firewall Management Center (FMC) Software could allow an unauthenticated, remote attacker to bypass authentication and execute script files on an affected device to obtain root access to the underlying operating system.  This vulnerability is due to an improper system process that is created at boot time. An attacker could exploit this vulnerability by sending crafted HTTP requests to an affected device. A successful exploit could allow the attacker to execute a variety of scripts and commands that allow root access to the device. 

Official EUVD record ↗

BSI · German · WID-SEC-2026-0610Cisco Secure Firewall Management Center: Mehrere Schwachstellen

Ein entfernter, authentisierter Angreifer kann mehrere Schwachstellen in Cisco Secure Firewall Management Center und Cisco Secure Firewall Threat Defense ausnutzen, um Root-Rechte zu erlangen, beliebigen Code mit Root-Rechten auszuführen, SQL-Injection durchzuführen und vertrauliche Daten offenzulegen sowie Daten zu manipulieren.

Official advisory ↗

Canadian Centre for Cyber Security · English · AV26-197Cisco security advisory (AV26-197) – Update 3

On March 4, 2026, Cisco published security advisories to address vulnerabilities in the following products. Included were critical updates for the following: On March 18, 2026, Cisco stated that CVE-2026-20131 is being actively exploited.

Official advisory ↗

Cyber Security Agency of Singapore · English · CSA-SB-20260311Security Bulletin 11 Mar 2026

The Cyber Security Agency of Singapore included this CVE in its official Security Bulletin 11 Mar 2026, published on 11 March 2026. Open the linked bulletin for the product, severity and reference information published in that issue.

Official advisory ↗

CERT-FR · French · CERTFR-2026-AVI-0242Multiples vulnérabilités dans les produits Cisco

De multiples vulnérabilités ont été découvertes dans les produits Cisco. Certaines d'entre elles permettent à un attaquant de provoquer une exécution de code arbitraire à distance, un déni de service à distance et une atteinte à la confidentialité des données.

Official advisory ↗

NBSZ-NKI · Hungarian · cve-2026-20079CVE-2026-20079

Kritikus

Official advisory ↗

CSIRT Italia · Italian · risolte-vulnerabilita-in-prodotti-cisco-19Risolte vulnerabilità in prodotti Cisco

Cisco ha rilasciato aggiornamenti di sicurezza che risolvono diverse nuove vulnerabilità, di cui due con gravità “critica” e 15 con gravità “alta”, riguardanti vari prodotti Secure Firewall.

Official advisory ↗

KISA KrCERT/CC · Korean · KNVD-6948美 CISA 발표 주요 Exploit 정보공유(Update. 2026-09-09)

Cisco Firewall Management Center Authentication Bypass Using an Alternate Path or Channel Vulnerability

Official advisory ↗

KISA KrCERT/CC · Korean · KNVD-6720Cisco 제품 보안 업데이트 권고

Cisco Secure Firewall Management Center (FMC) Software에서 발생하는 인증 우회 및 스크립트 실행 취약점(CVE-2026-20079) [1][3]

Official advisory ↗

NCSC-NL · Dutch · NCSC-2026-0076Kwetsbaarheden verholpen in Cisco Secure Firewall Management Center

De kwetsbaarheid met kenmerk CVE-2026-20079 bevindt zich in de webinterface van Cisco Secure Firewall Management Center. Een ongeauthenticeerde externe kwaadwillende kan de authenticatiecontroles omzeilen door een onjuist systeemproces dat bij het opstarten is aangemaakt te misbruiken. De kwaadwillende kan deze kwetsbaarheid misbruiken door speciaal geprepareerde HTTP-verzoeken naar een getroffen apparaat te sturen. Een succesvolle exploit kan de aanvaller in staat stellen verschillende scripts en commando’s uit te voeren die root-toegang tot het apparaat mogelijk maken. De kwetsbaarheid met kenmerk CVE-2026-20131 bevindt zich in de webinterface van Cisco Secure Firewall Management Center. Deze kwetsbaarheid stelt ongeauthenticeerde externe kwaadwillende in staat om willekeurige Java-code uit te voeren met root-rechten. De kwetsbaarheid wordt veroorzaakt door de onveilige deserialisatie van door de gebruiker aangeleverde Java-byte-stromen. Een kwaadwillende kan deze kwetsbaarheid misbruiken door een speciaal geprepareerd, geserialiseerd Java-object naar de webgebaseerde beheerinterface van een getroffen apparaat te sturen. Een succesvolle exploit kan de aanvaller in staat stellen om willekeurige code op het apparaat uit te voeren en de rechten te verhogen tot root-niveau. Als de beheerinterface van Cisco Secure Firewall Management Center geen publieke internettoegang heeft, wordt het aanvalsoppervlak verkleind. Het is niet gebruikelijk om een managementinterface direct publiekelijk aan het internet bloot te stellen. Indien jouw organisatie gebruikmaakt van Cisco Security Cloud Control Firewall Management, dan betreft dit een SaaS-dienst (Software-as-a-Service) die door Cisco Systems automatisch wordt bijgewerkt als onderdeel van regulier onderhoud. Er is in dat geval geen actie van de gebruiker vereist. Het NCSC verwacht op korte termijn een publieke PoC en grootschalige pogingen tot misbruik. Het NCSC adviseert met klem de update zo spoedig mogelijk te installeren. Update 19-03-26: Uit onderzoek van Amazon threat intelligence blijkt dat CVE-2026-20131 vermoedelijk al sinds 26 januari actief is misbruikt voor het uitrollen van Interlock ransomware. Daarnaast is er inmiddels een publieke PoC verschenen voor kwetsbaarheid CVE-2026-20079. Het is daarom van groot belang om - indien dit nog niet gedaan is - te updaten naar de nieuwste versie van Cisco Secure Firewall Management Center. **UPDATE 11-09-26:** Cisco meldt dat succesvolle exploitatie van de kwetsbaarheid met kenmerk CVE-2026-20079 is waargenomen. Organisaties wordt geadviseerd de updates van Csco direct toe te passen en kwetsbare systemen te controleren op aanwijzingen van misbruik. Raadpleeg de blog Talos voor aanvullende aanbevelingen. **EINDE UPDATE**

Official advisory ↗

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 not verified
Affected: Cisco Secure Firewall Management Center (FMC): 7.0.0, 7.0.0.1, 7.0.1, 7.1.0, 7.0.1.1, 7.1.0.1, 7.0.2, 7.2.0, 7.0.2.1, 7.0.3, 7.1.0.2, 7.2.0.1, 7.0.4, 7.2.1, 7.0.5, 7.3.0, 7.2.2, 7.3.1, 7.2.3, 7.1.0.3, 7.2.3.1, 7.2.4, 7.0.6, 7.2.4.1, 7.2.5, 7.3.1.1, 7.4.0, 7.0.6.1, 7.2.5.1, 7.4.1, 7.2.6, 7.4.1.1, 7.0.6.2, 7.2.7, 7.2.5.2, 7.3.1.2, 7.2.8, 7.6.0, 7.4.2, 7.2.8.1, 7.0.6.3, 7.4.2.1, 7.2.9, 7.0.7, 7.7.0, 7.4.2.2, 7.2.10, 7.6.1, 7.4.2.3, 7.0.8, 7.6.2, 7.7.10, 7.2.10.1, 7.0.8.1, 7.6.2.1, 7.2.10.2, 7.7.10.1, 7.4.2.4, 7.4.3, 7.7.11, 7.6.4, 10.0.0, 7.4.4, 7.4.5, 7.0.9, 7.2.11, 7.7.12, 7.6.5, 7.4.6, 10.0.1, 7.4.7
Fixed: No fixed version is explicitly recorded in the structured CVE data.
Action: No verified patch reference is present in the current structured sources. Check the vendor advisory before making a change.
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.

Evidence and provenance

Published 4 Mar 2026 · Last source change 26 Aug 2026, 16:28 UTC · CWE-288 · Authentication Bypass Using an Alternate Path or Channel

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 2026-08-14

European sourceENISA EUVD · EUVD-2026-9438

Product sourceCNA

Remediation sourceCVE/CNA references

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 ↗

26 Aug 2026, 16:28 UTC
Affected versionsThe structured affected or fixed version information changed.
Before
Cisco Secure Firewall Management Center (FMC): 7.0.0, 7.0.0.1, 7.0.1, 7.1.0, 7.0.1.1, 7.1.0.1, 7.0.2, 7.2.0, 7.0.2.1, 7.0.3, 7.1.0.2, 7.2.0.1, 7.0.4, 7.2.1, 7.0.5, 7.3.0, 7.2.2, 7.3.1, 7.2.3, 7.1.0.3, 7.2.3.1, 7.2.4, 7.0.6, 7.2.4.1, 7.2.5, 7.3.1.1, 7.4.0, 7.0.6.1, 7.2.5.1, 7.4.1, 7.2.6, 7.4.1.1, 7.0.6.2, 7.2.7, 7.2.5.2, 7.3.1.2, 7.2.8, 7.6.0, 7.4.2, 7.2.8.1, 7.0.6.3, 7.4.2.1, 7.2.9, 7.0.7, 7.7.0, 7.4.2.2, 7.2.10, 7.6.1, 7.4.2.3, 7.0.8, 7.6.2, 7.7.10, 7.2.10.1, 7.0.8.1, 7.6.2.1, 7.2.10.2, 7.7.10.1, 7.4.2.4, 7.4.3, 7.6.3, 7.7.11, 7.6.4, 10.0.0, 7.4.4, 7.4.5, 7.0.9, 7.2.11, 7.7.12, 7.6.5, 7.4.6, 10.0.1, 7.4.7 · Fixed: No fixed version is explicitly recorded in the structured CVE data.
After
Cisco Secure Firewall Management Center (FMC): 7.0.0, 7.0.0.1, 7.0.1, 7.1.0, 7.0.1.1, 7.1.0.1, 7.0.2, 7.2.0, 7.0.2.1, 7.0.3, 7.1.0.2, 7.2.0.1, 7.0.4, 7.2.1, 7.0.5, 7.3.0, 7.2.2, 7.3.1, 7.2.3, 7.1.0.3, 7.2.3.1, 7.2.4, 7.0.6, 7.2.4.1, 7.2.5, 7.3.1.1, 7.4.0, 7.0.6.1, 7.2.5.1, 7.4.1, 7.2.6, 7.4.1.1, 7.0.6.2, 7.2.7, 7.2.5.2, 7.3.1.2, 7.2.8, 7.6.0, 7.4.2, 7.2.8.1, 7.0.6.3, 7.4.2.1, 7.2.9, 7.0.7, 7.7.0, 7.4.2.2, 7.2.10, 7.6.1, 7.4.2.3, 7.0.8, 7.6.2, 7.7.10, 7.2.10.1, 7.0.8.1, 7.6.2.1, 7.2.10.2, 7.7.10.1, 7.4.2.4, 7.4.3, 7.7.11, 7.6.4, 10.0.0, 7.4.4, 7.4.5, 7.0.9, 7.2.11, 7.7.12, 7.6.5, 7.4.6, 10.0.1, 7.4.7 · Fixed: No fixed version is explicitly recorded in the structured CVE data.
CNA ↗
26 Aug 2026, 16:28 UTC
Public exploit evidencePublic exploit evidence changed from Public exploit reference to Public exploit reference.
Before
Public exploit reference
After
Public exploit reference
af854a3a-2127-422b-91ae-364da2661108 ↗
10 Sept 2026, 03:55 UTC
Affected versionsThe structured affected or fixed version information changed.
Before
7.0.0; 7.0.0.1; 7.0.1; 7.1.0; 7.0.1.1; 7.1.0.1; 7.0.2; 7.2.0 · Fixed: No fixed version is explicitly recorded in the structured CVE data.
After
Cisco Secure Firewall Management Center (FMC): 7.0.0, 7.0.0.1, 7.0.1, 7.1.0, 7.0.1.1, 7.1.0.1, 7.0.2, 7.2.0, 7.0.2.1, 7.0.3, 7.1.0.2, 7.2.0.1, 7.0.4, 7.2.1, 7.0.5, 7.3.0, 7.2.2, 7.3.1, 7.2.3, 7.1.0.3, 7.2.3.1, 7.2.4, 7.0.6, 7.2.4.1, 7.2.5, 7.3.1.1, 7.4.0, 7.0.6.1, 7.2.5.1, 7.4.1, 7.2.6, 7.4.1.1, 7.0.6.2, 7.2.7, 7.2.5.2, 7.3.1.2, 7.2.8, 7.6.0, 7.4.2, 7.2.8.1, 7.0.6.3, 7.4.2.1, 7.2.9, 7.0.7, 7.7.0, 7.4.2.2, 7.2.10, 7.6.1, 7.4.2.3, 7.0.8, 7.6.2, 7.7.10, 7.2.10.1, 7.0.8.1, 7.6.2.1, 7.2.10.2, 7.7.10.1, 7.4.2.4, 7.4.3, 7.6.3, 7.7.11, 7.6.4, 10.0.0, 7.4.4, 7.4.5, 7.0.9, 7.2.11, 7.7.12, 7.6.5, 7.4.6, 10.0.1, 7.4.7 · Fixed: No fixed version is explicitly recorded in the structured CVE data.
CNA ↗
10 Sept 2026, 03:55 UTC
Public exploit evidencePublic exploit evidence changed from Public exploit reference to Public exploit reference.
Before
Public exploit reference
After
Public exploit reference
134c704f-9b21-4f2e-91b3-4a467353bcc0 ↗
10 Sept 2026, 12:07 UTC
ENISA known-exploited stateENISA EUVD now records this CVE in its known-exploited dataset.
Before
not recorded
After
{"euvdId":"EUVD-2026-9438","listed":true,"sources":["cisa_kev"]}
ENISA EUVD ↗
10 Sept 2026, 08:04 UTC
BlackTree coverageBlackTree article coverage changed from no BlackTree article to 1 BlackTree article.
Before
no BlackTree article
After
1 BlackTree article
BlackTree editorial ↗
9 Sept 2026, 16:07 UTC
CISA KEV stateCISA KEV now confirms exploitation in the wild.
Before
not listed in CISA KEV
After
listed in CISA KEV since 2026-09-09
CISA KEV ↗
9 Sept 2026, 16:07 UTC
Vendor guidanceAuthoritative vendor guidance changed from no authoritative guidance recorded to vendor advisory.
Before
no authoritative guidance recorded
After
vendor advisory
psirt@cisco.com ↗
9 Sept 2026, 16:07 UTC
Public exploit evidencePublic exploit evidence changed from No public exploit to Public exploit reference.
Before
No public exploit
After
Public exploit reference
af854a3a-2127-422b-91ae-364da2661108 ↗

2026-03-04CVE published

2026-09-09Added to CISA KEV

ENISA EUVD · EUVD-2026-9438↗CISA KEV record↗CVE authority or vendor reference↗Public exploit reference↗Public exploit reference↗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.

Cisco Firewall Management Center Authentication Bypass Using an Alternate Path or Channel Vulnerability

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

ENISA European Vulnerability Database

EUVD-2026-9438

What, why and how

Exploit reality and attack path

Official authority intelligence

Patch and workaround

Evidence and provenance

What changed after publication

Cisco Firewall Management Center Authentication Bypass Using an Alternate Path or Channel Vulnerability

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

EUVD-2026-9438

What, why and how

Exploit reality and attack path

Official authority intelligence

Patch and workaround

Evidence and provenance

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