CVE-2026-75943: CWE-459 Incomplete Cleanup in Arista Networks EOS
A brief (milliseconds to seconds) traffic leak may occur when an authenticated supplicant is removed, either via the clear dot1x host all CLI command or due to a supplicant timeout. During this window, the supplicant's traffic may pass without ACL enforcement.
AI Analysis
Technical Summary
This vulnerability (CWE-459: Incomplete Cleanup) in Arista Networks EOS causes a short window of traffic leakage after an authenticated supplicant is removed. During this brief period, the supplicant's traffic may not be subject to ACL enforcement, potentially allowing unauthorized traffic flow. The vulnerability affects multiple EOS versions ranging from 0.0.0 up to 4.36.1F, including several intermediate versions. The CVSS 3.1 base score is 2.6, indicating low severity, with attack vector as adjacent network, high attack complexity, low privileges required, no user interaction, unchanged scope, no confidentiality impact, low integrity impact, and no availability impact.
Potential Impact
The impact is limited to a brief traffic leak where ACL enforcement is temporarily bypassed for a removed supplicant. There is no confidentiality or availability impact, and the integrity impact is low. No known exploits are reported in the wild.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until a fix is available, avoid using the clear dot1x host all CLI command unnecessarily and monitor supplicant removal processes. Follow vendor guidance once published.
CVE-2026-75943: CWE-459 Incomplete Cleanup in Arista Networks EOS
Description
A brief (milliseconds to seconds) traffic leak may occur when an authenticated supplicant is removed, either via the clear dot1x host all CLI command or due to a supplicant timeout. During this window, the supplicant's traffic may pass without ACL enforcement.
CVSS v3.1
Score 2.6low
Affected software
Arista Networks
EOS
pkg:github/arista-networks/eosRun on your own infrastructure? Check whether these packages are installed with threat-finder — our free open-source scanner.
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability (CWE-459: Incomplete Cleanup) in Arista Networks EOS causes a short window of traffic leakage after an authenticated supplicant is removed. During this brief period, the supplicant's traffic may not be subject to ACL enforcement, potentially allowing unauthorized traffic flow. The vulnerability affects multiple EOS versions ranging from 0.0.0 up to 4.36.1F, including several intermediate versions. The CVSS 3.1 base score is 2.6, indicating low severity, with attack vector as adjacent network, high attack complexity, low privileges required, no user interaction, unchanged scope, no confidentiality impact, low integrity impact, and no availability impact.
Potential Impact
The impact is limited to a brief traffic leak where ACL enforcement is temporarily bypassed for a removed supplicant. There is no confidentiality or availability impact, and the integrity impact is low. No known exploits are reported in the wild.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until a fix is available, avoid using the clear dot1x host all CLI command unnecessarily and monitor supplicant removal processes. Follow vendor guidance once published.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- Arista
- Date Reserved
- 2026-08-18T16:04:10.264Z
- Cvss Version
- 3.1
- State
- PUBLISHED
Threat ID: 6aa875f055bf5e2cf5ba9994
Added to database: 09/14/2026, 22:32:16 UTC
Last enriched: 09/14/2026, 22:46:47 UTC
Last updated: 09/15/2026, 03:14:17 UTC
Views: 8
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