CVE-2026-76459Cisco NX-OS Software Security Hardening Release: October 2026 - Out-of-bounds Write Vulnerabilities
- 9.8CriticalCVSS base score
- 0.33%Exploitation in 30 daysEPSS · top 74% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- NonePublic exploitsnone known yet
Description
As part of Cisco's ongoing commitment to proactive security and product quality, the Cisco NX-OS engineering team has conducted a comprehensive internal security review. This review resulted in a software hardening release that addresses multiple internally discovered vulnerabilities. The vulnerabilities tracked by CVE-2026-76459 are related to out-of-bounds write issues that are grouped under the Common Weakness Enumeration (CWE) CWE-787.
Timeline
ID reserved
By cisco
- 49 days later
· 49 days later
Published
- 31 days later
· 31 days later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| ciscoCNA (assigner) | 3.1 | Critical9.8 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
| NVDNVD · Awaiting Analysis | 3.1 | Critical9.8 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
- EPSS (exploitation in 30 days)
- 0.33% · top 74% of all CVEs (12 Nov 2026)
- CISA SSVC
- Exploitation: none · Automatable: no · Technical impact: total
The list uses the assigner's score when there is one, then CISA's, then NVD's: Critical 9.8.
Affected products
- affected 8.2(5)
- affected 7.3(5)D1(1)
- affected 8.4(2)
- affected 8.4(3)
- affected 9.2(3)
- affected 8.2(1)
- affected 7.3(1)D1(1)
- affected 9.2(2v)
- affected 7.3(0)D1(1)
- affected 7.3(4)D1(1)
- affected 9.2(1)
- affected 9.2(2t)
- affected 9.2(3y)
- affected 9.3(2)
- affected 7.3(1)DY(1)
- affected 8.1(1)
- affected 8.2(2)
- affected 8.3(2)
- affected 7.3(2)D1(3a)
- affected 9.2(4)
- affected 8.1(2)
- affected 7.3(3)D1(1)
- affected 8.2(3)
- affected 8.3(1)
- affected 8.4(1)
- affected 8.1(1b)
- affected 7.3(0)DX(1)
- affected 7.3(2)D1(1)
- affected 9.3(1)
- affected 7.3(2)D1(2)
- affected 8.2(4)
- affected 7.3(0)DY(1)
- affected 9.3(1z)
- affected 9.2(2)
- affected 8.1(2a)
- affected 7.3(2)D1(3)
- affected 8.1(1a)
- affected 8.4(1a)
- affected 9.3(3)
- affected 7.3(2)D1(1d)
- and 106 more
Cisco · Cisco NX-OS System Software in ACI Mode
- affected 15.2(1g)
- affected 15.2(2e)
- affected 15.2(2f)
- affected 15.2(2g)
- affected 15.2(2h)
- affected 15.2(3f)
- affected 15.2(3e)
- affected 15.2(3g)
- affected 15.2(4d)
- affected 15.2(4e)
- affected 15.2(5c)
- affected 15.2(5d)
- affected 16.0(1g)
- affected 15.2(5e)
- affected 15.2(4f)
- affected 15.2(6e)
- affected 15.2(6h)
- affected 16.0(1j)
- affected 15.2(6g)
- affected 15.2(7f)
- affected 15.2(7g)
- affected 16.0(2h)
- affected 15.2(8d)
- affected 16.0(2j)
- affected 15.2(8e)
- affected 16.0(3d)
- affected 16.0(3e)
- affected 15.2(8f)
- affected 15.2(8g)
- affected 15.3(1d)
- affected 15.2(8h)
- affected 16.0(4c)
- affected 15.3(2a)
- affected 15.2(8i)
- affected 16.0(5h)
- affected 15.3(2b)
- affected 16.0(3g)
- affected 16.0(5j)
- affected 15.3(2c)
- affected 16.0(6c)
- and 21 more
Cisco · Cisco Unified Computing System (Managed)
- affected 4.0(1a)
- affected 4.1(1d)
- affected 4.0(4f)
- affected 4.0(4c)
- affected 4.0(2b)
- affected 4.1(2a)
- affected 4.0(4a)
- affected 4.0(4e)
- affected 4.0(4h)
- affected 4.0(2a)
- affected 4.1(1c)
- affected 4.0(1b)
- affected 4.1(1e)
- affected 4.0(4d)
- affected 4.0(4b)
- affected 4.0(2e)
- affected 4.1(1a)
- affected 4.0(4g)
- affected 4.0(1d)
- affected 4.0(1c)
- affected 4.0(4i)
- affected 4.0(2d)
- affected 4.1(1b)
- affected 4.1(2b)
- affected 4.0(4k)
- affected 4.1(3a)
- affected 4.1(3b)
- affected 4.1(2c)
- affected 4.0(4l)
- affected 4.1(4a)
- affected 4.1(3c)
- affected 4.1(3d)
- affected 4.2(1c)
- affected 4.2(1d)
- affected 4.0(4m)
- affected 4.1(3e)
- affected 4.2(1f)
- affected 4.1(3f)
- affected 4.2(1i)
- affected 4.1(3h)
- and 65 more
What to do
Exploitation: The Cisco PSIRT is not aware of any public announcements or malicious use of the vulnerabilities that are described in this advisory.
References
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- EUVD EUVD-2026-94462 (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://cveledger.app/cve/CVE-2026-76459)Record last updated .