CVE-2024-27891: Arista Networks EOS · Improper Access Control
Affects Arista Networks EOSSource CVE Database V5
Not known to be exploited · CVSS 6.9 Medium : upgrade to 4.28.0 when convenient.
Data as of 26 Oct 2026, 10:12 UTC
- EPSS
- 0.2% chance of exploitation in 30 days – higher than 20% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 4.28.0
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:NExploitation evidence
Disclosed: evidence found.
CVE published 4 Jun 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.
What to do
Upgrade Arista Networks EOS to 4.28.0.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| Arista NetworksEOS | Affected
| Fixed in
|
AI-suggested
If you cannot patch yet, administrators should review configurations involving MACsec and egress ACLs on the same interfaces and consider temporary workarounds such as disabling one of these features on the same interface if feasible.
Description
CVE-2024-27891 is a medium severity vulnerability in Arista Networks EOS where ACL policies may not be enforced on egressing packets if MACsec and egress ACLs are configured on the same interfaces. This improper access control can cause packets to be incorrectly allowed or denied when leaving the affected ports.