CVE Intelligence
Critical Memory corruption

CVE-2026-76501 — Cisco Nexus 9000 Series Switches SRv6 OAM (NGOAM) Remote Code Execution Vulnerability

A vulnerability in the Segment Routing over IPv6 (SRv6) Operation, Administration, and Maintenance (OAM) feature of Cisco NX-OS Software, known as NGOAM, could allow an unauthenticated, remote attacker to execute arbitrary code with root privileges or cause a denial of service (DoS) on an affected device. This vulnerability is due to improper input validation of IP traffic when the NGOAM and SRv6 features are enabled. An attacker could exploit this vulnerability by sending crafted packets to an IP interface on an affected device. A successful exploit could allow the attacker to execute arbitrary code with root privileges and could cause process crashes resulting in a reload and DoS condition.

Published Oct 7, 2026 · Updated Oct 13, 2026 · Sources: NIST National Vulnerability Database, CVE Program (cve.org) e CISA ADP · CNA: cisco

Who exploits it and how urgent it is

A 0–100 score combining confirmed exploitation, ransomware and APT use, public exploits, EPSS and severity.

No exploitation signal in the sources consulted so far.
How the score was calculated
  • EPSS 0.5% (30-day exploitation probability)+6
  • Technical severity (critical)+10
  • Automatable exploitation (SSVC)+3

The score orders the patch queue; it does not replace your asset context (internet exposure, criticality, compensating controls).

Triage

Is it exploited, how likely is exploitation, what does it touch, and how severe do the sources call it.

Exploitation
Not confirmed
Not in CISA KEV — an absence of record, not proof it is unexploited.
EPSS FIRST
0.51%
ahead of 42% of scored CVEs · Oct 14, 2026
Affects
Cisco
Cisco NX-OS Software
CVSS base
9.8
Critical · 2 source(s)

CISA SSVC assessment CISA

Three decision points CISA publishes for the CVEs it assesses (SSVC 2.0.3). A stakeholder decision, not a severity score.

Exploitation
None
none · proof-of-concept · active
Automatable
Yes
can an attacker script the kill-chain steps
Technical impact
Total
partial · total control of the vulnerable component

Remediation

Fixes and mitigations documented by the sources — linked to the original advisory.

No fix documented by the sources we poll. That does not mean none exists: check the vendor advisory.

First 24 hours

Ordered from the record’s own fields — exposure first, because you cannot patch what you have not found. A rule-generated starting point.

  1. Identify exposed assets running the affected vendor/product/version combinations (Cisco Cisco NX-OS Software).
  2. The attack is network-based and needs no privileges: restrict exposure (ACLs, VPN, WAF) until patched.
  3. No fix documented in the sources: reduce exposure and monitor the vendor advisory.
  4. Search available logs for exploit probes matching the vulnerability class (memory corruption), errors and authentication anomalies.

Affected scope

Vendor, product and versions as the sources word them.

VendorProductVersionsStatusSource
Cisco Cisco NX-OS Software version 10.4(6)version 10.3(3r)version 10.3(6)version 9.3(14)version 10.4(4)version 10.3(4h)version 10.5(2)version 10.3(7)
and 55 more version 10.4(5)version 10.5(3)version 9.3(15)version 10.4(4g)version 10.5(4)version 10.6(1)version 10.5(3t)version 10.3(8)version 10.5(1)version 10.5(3s)version 10.5(3e)version 10.5(3o)version 9.3(16)version 10.6(1s)version 10.6(2)version 10.5(3p)version 10.3(9)version 10.6(2s)version 10.6(3)version 10.4(7)version 10.5(5)version 9.3(17)version 10.6(2n)version 10.6(3s)version 10.4(1)version 9.3(4)version 9.3(5)version 9.3(6)version 9.3(5w)version 9.3(7)version 9.3(7k)version 9.3(7a)version 9.3(8)version 9.3(9)version 9.3(10)version 10.3(1)version 10.3(2)version 9.3(11)version 10.3(3)version 9.3(12)version 9.3(3)version 10.3(99w)version 10.3(3w)version 10.3(99x)version 10.3(3o)version 10.3(4)version 10.3(3p)version 10.3(4a)version 10.4(2)version 10.3(3q)version 9.3(13)version 10.3(5)version 10.4(3)version 10.3(3x)version 10.3(4g)
Vulnerable CVE Program (cve.org) e CISA ADP

Attack characteristics

The CVSS vector, decoded. It describes the attack, not your exposure to it.

Attack vector
Network
Attack complexity
Low
Privileges required
None
User interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High

Every base score collected

Sources score independently and may disagree; each row says who scored it and under which version.

ScoreVersionSeverityExpl.ImpactScored by
9.8 CVSS 3.1 Critical 3.9 5.9 psirt@cisco.com via NIST National Vulnerability Database
9.8 CVSS 3.1 Critical — — cisco via CVE Program (cve.org) e CISA ADP
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H (score shown at the top: psirt@cisco.com)

Weakness MITRE

Weakness class according to MITRE’s CWE catalog.

CWE-121 · Stack-based Buffer Overflow

Other CVEs with this weakness →

EPSS over time FIRST

Oct 13, 2026 → Oct 14, 2026 · 2 reading(s) · max 0.51%

Detection

Read off the CVSS vector and the weakness class. Starting points, not tested rules.

  • Prioritize edge telemetry for the network-reachable component (proxy, WAF, IDS/IPS).
  • Correlate service crashes/restarts with inbound traffic; repeated crashes may indicate attempts.
web/proxy/WAF logsnetwork IDS/IPSendpoint telemetry (EDR)crash dumps

Timeline

What happened to this CVE, newest first.

  • 2026
  • Affected products added · cisco/cisco nx-os software
    Oct 13, 2026 · CVE Program (cve.org) e CISA ADP
  • SSVC assessment updated
    Oct 13, 2026 · CVE Program (cve.org) e CISA ADP
  • Record published
    Oct 13, 2026
  • CVSS changed · 9.8
    Oct 13, 2026 · NIST National Vulnerability Database
  • Source status changed · → Awaiting Analysis
    Oct 13, 2026 · NIST National Vulnerability Database
  • Record created in this database
    Oct 13, 2026 · NIST National Vulnerability Database
  • CVE published
    Oct 7, 2026 · cisco

Source activity

Repeated readings are counted rather than listed.

  • 1× Official description updated · Oct 13, 2026 – Oct 13, 2026

References

1 on the record

Elsewhere on this site

Cisco
every CVE for this vendor
Memory corruption
same class
CWE-121
other pages naming this weakness

Related CVEs (same products)

  • CVE-2026-76486 Cisco Nexus 3000 and 9000 Series Switches VXLAN OAM (NGOAM) Remote Code Execution Vulnerability 8d
  • CVE-2026-76485 Cisco Nexus 3000 and 9000 Series Switches VXLAN OAM (NGOAM) Remote Code Execution Vulnerability 8d
  • CVE-2026-76471 Cisco NX-OS Software NX-API Remote Code Execution Vulnerability 8d
  • CVE-2026-76465 Cisco Nexus 3000 and 9000 Series Switches MPLS OAM Remote Code Execution Vulnerability 8d
  • CVE-2026-76459 Cisco NX-OS Software Security Hardening Release: October 2026 - Out-of-bounds Write Vulnerabilities 8d
  • CVE-2026-76458 Cisco NX-OS Software Security Hardening Release: October 2026 - Improper Handling of Exceptional Conditions Vulnerabilities 8d

Not in any source we poll

Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.

  • No fixed version, patch or mitigation documented.
  • No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
  • No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
  • No exploit packet captures, log samples, or incident case IDs supplied.

Answered from this record

Text assembled only from the fields above — no additional claims.

What should defenders know first?

CVE-2026-76501 is "Cisco Nexus 9000 Series Switches SRv6 OAM (NGOAM) Remote Code Execution Vulnerability", rated Critical. It affects Cisco NX-OS Software (Cisco); versions are in the scope table. It is not in CISA KEV, which does not rule out exploitation. CVSS 9.8 describes technical severity. EPSS 0.51% estimates the probability of exploitation in 30 days; neither replaces your asset context. First verify whether exposed or business-critical assets run the affected versions, apply vendor fixes or mitigations, and preserve logs for review.

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