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Full vulnerability report · 2018
CVE-2018-0305High confidence

n/a Cisco FXOS and NX-OS unknown: NULL Pointer Dereference

Unknown · Cisco FXOS and NX-OS unknown

Official source article: Cisco CISCO-SA-20180620-FX-OS-FABRIC-DOS ↗. Check the applicable product and release in the original source.

8.6HighCVSS 3.0
Recommended action
Within 7 days

High technical severity; prioritise exposed affected systems while verifying vendor guidance.

Fix not verified
R
Operational reassessment

Published severity in operational context

Open reassessment dashboard →
Published severityHighOperational priority:High, unchanged from published severity.unchanged

Evidence used

  • No CISA KEV confirmation is currently recorded.
  • The selected CVSS metric records a network-reachable, unauthenticated path with no user interaction.
  • EPSS is 2.27% for the current model date.

Compensating controls

  • Restrict the affected network interface to trusted sources where business-safe.
  • Monitor vendor guidance and exploitation sources for a material change.

Verification

  1. Confirm that the asset runs Unknown Cisco FXOS and NX-OS unknown and falls inside the recorded affected range.
  2. Recheck the vendor advisory before scheduling a change because no verified fixed version is currently retained.
  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 30 daysRemediation target: Within 180 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.

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-2018-1128

No EUVD known-exploited evidence

ENISA has published the identifier mapping but no EUVD description has been stored yet.

EUVD state
Present in the current official mapping
Known exploitation
Not present in the current ENISA EUVD known-exploited dataset. This is not proof of no exploitation.
ENISA score
Not supplied in the stored EUVD record
Advisory evidence
No linked advisory details stored yet
Recommended actionWithin 7 days

High technical severity; prioritise exposed affected systems while verifying vendor guidance.

Fix not verified
01

What, why and how

A vulnerability in the Cisco Fabric Services component of Cisco FXOS Software and Cisco NX-OS Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on the affected device. The vulnerability exists because the affected software insufficiently validates Cisco Fabric Services packets. An attacker could exploit this vulnerability by sending a crafted Cisco Fabric Services packet to an affected device. A successful exploit could allow the attacker to force a NULL pointer dereference and cause a DoS condition. This vulnerability affects the following if configured to use Cisco Fabric Services: Firepower 4100 Series Next-Generation Firewalls, Firepower 9300 Security Appliance, MDS 9000 Series Multilayer Switches, Nexus 2000 Series Fabric Extenders, Nexus 3000 Series Switches, Nexus 3500 Platform Switches, Nexus 5500 Platform Switches, Nexus 5600 Platform Switches, Nexus 6000 Series Switches, Nexus 7000 Series Switches, Nexus 7700 Series Switches, Nexus 9000 Series Switches in standalone NX-OS mode, Nexus 9500 R-Series Line Cards and Fabric Modules, UCS 6100 Series Fabric Interconnects, UCS 6200 Series Fabric Interconnects, UCS 6300 Series Fabric Interconnects. Cisco Bug IDs: CSCvd69966, CSCve02435, CSCve04859, CSCve41590, CSCve41593, CSCve41601.

What

A vulnerability in the Cisco Fabric Services component of Cisco FXOS Software and Cisco NX-OS Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on the affected device. The vulnerability exists because the affected software insufficiently validates Cisco Fabric Services packets. An attacker could exploit this vulnerability by sending a crafted Cisco Fabric Services packet to an affected device. A successful exploit could allow the attacker to force a NULL pointer dereference and cause a DoS condition. This vulnerability affects the following if configured to use Cisco Fabric Services: Firepower 4100 Series Next-Generation Firewalls, Firepower 9300 Security Appliance, MDS 9000 Series Multilayer Switches, Nexus 2000 Series Fabric Extenders, Nexus 3000 Series Switches, Nexus 3500 Platform Switches, Nexus 5500 Platform Switches, Nexus 5600 Platform Switches, Nexus 6000 Series Switches, Nexus 7000 Series Switches, Nexus 7700 Series Switches, Nexus 9000 Series Switches in standalone NX-OS mode, Nexus 9500 R-Series Line Cards and Fabric Modules, UCS 6100 Series Fabric Interconnects, UCS 6200 Series Fabric Interconnects, UCS 6300 Series Fabric Interconnects. Cisco Bug IDs: CSCvd69966, CSCve02435, CSCve04859, CSCve41590, CSCve41593, CSCve41601.

Why

The product dereferences a pointer that it expects to be valid but is NULL.

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

A vulnerability in the Cisco Fabric Services component of Cisco FXOS Software and Cisco NX-OS Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on the affected device. The vulnerability exists because the affected software insufficiently validates Cisco Fabric Services packets. An attacker could exploit this vulnerability by sending a crafted Cisco Fabric Services packet to an affected device. A successful exploit could allow the attacker to force a NULL pointer dereference and cause a DoS condition. This vulnerability affects the following if configured to use Cisco Fabric Services: Firepower 4100 Series Next-Generation Firewalls, Firepower 9300 Security Appliance, MDS 9000 Series Multilayer Switches, Nexus 2000 Series Fabric Extenders, Nexus 3000 Series Switches, Nexus 3500 Platform Switches, Nexus 5500 Platform Switches, Nexus 5600 Platform Switches, Nexus 6000 Series Switches, Nexus 7000 Series Switches, Nexus 7700 Series Switches, Nexus 9000 Series Switches in standalone NX-OS mode, Nexus 9500 R-Series Line Cards and Fabric Modules, UCS 6100 Series Fabric Interconnects, UCS 6200 Series Fabric Interconnects, UCS 6300 Series Fabric Interconnects. Cisco Bug IDs: CSCvd69966, CSCve02435, CSCve04859, CSCve41590, CSCve41593, CSCve41601.

Why

The product dereferences a pointer that it expects to be valid but is NULL.

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.
No confirmed evidence

No CISA KEV match was present at the last successful refresh. This means no confirmation from that source, not proof of no exploitation.

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 → 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-476 ↗

CWE-476: NULL Pointer Dereference. The product dereferences a pointer that it expects to be valid but is NULL.

CVSS vector
?CVSS means Common Vulnerability Scoring System. The vector records the metric values used to calculate technical severity.
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H

Common Vulnerability Scoring System 3.0: 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-476
A

Official authority intelligence

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

Canadian Centre for Cyber Security · English · AV18-103Cisco security updates

cts TelePresence Video Communication Server (VCS) Expressway Unified Communications Manager IM & Presence Service Unified Communications Domain Manager NX-OS Software NVIDIA TX1 Web Admin Interface of Cisco Meeting Server Firepower Management Center AnyConnect Secure Mobility Client for Windows Desktop CVE References: CVE-2018-0301, CVE-2018-0308, CVE-2018-0304, CVE-2018-0314, CVE-2018-0312, CVE-2018-0307, CVE-2018-0291, CVE-2018-0293, CVE-2018-0292, CVE-2018-0295, CVE-2018-0294, CVE-2018-0294, CVE-2018-0331, CVE-2018-0311, CVE-2018-0310, CVE-2018-0306, CVE-2018-0313, CVE-2018-0299, CVE-2018-0309, CVE-2018-0298, CVE-2018-0302, CVE-2018-0303, CVE-2018-0305, CVE-2018-0300, CVE-2018-0358, CVE-2018-0363, CVE-2018-0364, CVE-2018-0337, CVE-2018-6242, CVE-2018-0371, CVE-2018-0365, CVE-2018-0362, CVE-2018-0359, CVE-2018-0373, CVE-2018-0330 Suggested Action CCIRC recommends that system administrators test and deploy the vendor-released updates to affected applications accordingly. References: https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20180620-nxos-bo https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20180620-fxnxos-fab-ace https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20180620-fx-os-fabric-execution http

Official advisory ↗
CERT-FR · French · CERTFR-2018-AVI-298Multiples vulnérabilités dans les produits Cisco

.cve.org/CVERecord?id=CVE-2018-0294 Référence CVE CVE-2018-0295 https://www.cve.org/CVERecord?id=CVE-2018-0295 Référence CVE CVE-2018-0298 https://www.cve.org/CVERecord?id=CVE-2018-0298 Référence CVE CVE-2018-0299 https://www.cve.org/CVERecord?id=CVE-2018-0299 Référence CVE CVE-2018-0300 https://www.cve.org/CVERecord?id=CVE-2018-0300 Référence CVE CVE-2018-0301 https://www.cve.org/CVERecord?id=CVE-2018-0301 Référence CVE CVE-2018-0302 https://www.cve.org/CVERecord?id=CVE-2018-0302 Référence CVE CVE-2018-0303 https://www.cve.org/CVERecord?id=CVE-2018-0303 Référence CVE CVE-2018-0304 https://www.cve.org/CVERecord?id=CVE-2018-0304 Référence CVE CVE-2018-0305 https://www.cve.org/CVERecord?id=CVE-2018-0305 Référence CVE CVE-2018-0306 https://www.cve.org/CVERecord?id=CVE-2018-0306 Référence CVE CVE-2018-0307 https://www.cve.org/CVERecord?id=CVE-2018-0307 Référence CVE CVE-2018-0308 https://www.cve.org/CVERecord?id=CVE-2018-0308 Référence CVE CVE-2018-0309 https://www.cve.org/CVERecord?id=CVE-2018-0309 Référence CVE CVE-2018-0310 https://www.cve.org/CVERecord?id=CVE-2018-0310 Référence CVE CVE-2018-0311 https://www.cve.org/CVERecord?id=CVE-2018-0311 Référence CVE CVE-2018-0312 https://www.cve.org/CVERecord?id=CVE-2018-0312 Référence CVE CVE-2018-0313 https://www.cve.org/CVERecord?id=CVE-2018-0313 Ré

Official advisory ↗
JVN iPedia · Japanese · JVNDB-2018-006583Cisco FXOS および NX-OS ソフトウェアにおける NULL ポインタデリファレンスに関する脆弱性

Cisco FXOS および NX-OS ソフトウェアには、NULL ポインタデリファレンスに関する脆弱性が存在します。 ベンダは、本脆弱性を Bug ID CSCvd69966、CSCve02435、CSCve04859、CSCve41590、CSCve41593、および CSCve41601 として公開しています。

Official advisory ↗
KISA KrCERT/CC · Korean · KNVD-4894Cisco 제품군 취약점 보안 업데이트 권고

(CVE-2018-0305) [23]

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 not verified
Affected
Cisco FXOS and NX-OS unknown: Cisco FXOS and NX-OS unknown
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.
04

Evidence and provenance

Published 21 Jun 2018 · Last source change 29 Nov 2024, 14:58 UTC · CWE-476 · NULL Pointer Dereference

CVE recordCVE.org · 5.1
CVSS sourceNIST NVD
EPSS source
?The date BlackTree first stored a score for this CVE from the daily FIRST EPSS feed.
FIRST · tracked since 2026-09-01
European sourceENISA EUVD · EUVD-2018-1128
Product sourceCNA
Remediation sourceCVE/CNA references
CWE sourceCNA
NVD statusNVD modified after enrichment

Missing structured fields: affected product. Missing data is not evidence of low risk; review the primary advisory.

Material change intelligence

What changed after publication

View recent updates ↗
  1. ENISA EUVD mappingEUVD-2018-1128 was added to the official ENISA EUVD mapping for this CVE.
    Before
    not recorded
    After
    {"euvdId":"EUVD-2018-1128"}
    ENISA EUVD ↗
  2. Vendor guidanceAuthoritative vendor guidance changed: added vendor advisory: tools.cisco.com/cisco-sa-20180620-fx-os-fabric-dos.
    Before
    no authoritative guidance recorded
    After
    vendor advisory: tools.cisco.com/cisco-sa-20180620-fx-os-fabric-dos
    tools.cisco.com ↗
  3. SeveritySeverity changed from Unknown to High.
    Before
    Unknown
    After
    High
    NIST NVD ↗
  4. CVSS scoreCVSS score changed from not recorded to 8.6 (CVSS 3.0 · NIST NVD · CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H).
    Before
    not recorded
    After
    8.6 (CVSS 3.0 · NIST NVD · CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H)
    NIST NVD ↗
  5. Catalogue recordCVE added to the BlackTree catalogue.
    CNA ↗
Material fields only · duplicate refreshes suppressed · history retained for the configured operational retention period
CVE published
ENISA EUVD · EUVD-2018-1128↗Vendor advisory · Cisco CISCO-SA-20180620-FX-OS-FABRIC-DOS↗CVE authority or vendor 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.
Free version - for non-commercial use only.CVE-2018-0305 · cve.blacktree.nl