CVE-2026-77191 json
All of the CVEs covered in this advisory apply to affected platforms running Arista EOS with 802.1X authentication and authorization enabled and Access Control Lists (ACLs) configured for per-supplicant policy enforcement. An authenticated supplicant on an
published last mo. modified last mo. also EUVD-2026-78203
- cvss
- 2.6
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.2%
- EPSS 0.2% chance of exploitation in 30 days, percentile 13%
- public exploits
- 0
- none known
Summary
An authenticated supplicant on an adjacent network may bypass intended network authorization policy and send unrestricted traffic during a brief window (milliseconds to seconds) between the completion of the authentication phase and the full enforcement of its assigned ACL.
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- Exploitation
- none
- Automatable
- no
- Technical impact
- partial
- Assessed
- last mo.
Exploit prediction
0.22% chance of exploitation in the next 30 days, higher than 13% of all scored CVEs (FIRST EPSS, 2026-11-11).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 2.6 | CVSS:3.1/AV:A/AC:H/PR:L/UI:N/S:U/C:N/I:L/A:N |
| CNA | 4.0 | 2.1 | CVSS:4.0/AV:A/AC:L/AT:P/PR:L/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N |
| CNA | 4.0 | 2.1 | CVSS:4.0/AV:A/AC:L/AT:P/PR:L/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X |
Affected products
- Arista Networks EOS
Classification
- Weakness
-
- CWE-862 Missing Authorization
References
Sources
- CVE List CVE-2026-77191
- NVD CVE-2026-77191
Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.