CVE-2026-73436: CWE-1284 Improper Validation of Specified Quantity in Input in Arista Networks EOS
On affected platforms running Arista EOS with OSPFv2 and OSPFv2 segment routing configured, a specially crafted OSPFv2 packet from an adjacent OSPF neighbor may cause OSPF to restart unexpectedly.
AI Analysis
Technical Summary
CVE-2026-73436 is a medium severity vulnerability in Arista Networks EOS affecting OSPFv2 with segment routing. It involves improper validation of input quantities in OSPFv2 packets, which may cause the OSPF process to restart unexpectedly when processing a specially crafted packet from an adjacent OSPF neighbor. This results in an availability impact without affecting confidentiality or integrity. The vulnerability affects EOS versions from 1.0.0 up to and including various subversions up to 4.36.1F. No vendor advisory or patch information is provided, so patch status is unknown.
Potential Impact
The vulnerability causes an unexpected restart of the OSPF process, resulting in a temporary denial of service affecting network availability. There is no impact on confidentiality or integrity. 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, monitoring OSPF stability and limiting adjacency with untrusted neighbors may reduce risk.
CVE-2026-73436: CWE-1284 Improper Validation of Specified Quantity in Input in Arista Networks EOS
Description
On affected platforms running Arista EOS with OSPFv2 and OSPFv2 segment routing configured, a specially crafted OSPFv2 packet from an adjacent OSPF neighbor may cause OSPF to restart unexpectedly.
CVSS v3.1
Score 6.5medium
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.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-73436 is a medium severity vulnerability in Arista Networks EOS affecting OSPFv2 with segment routing. It involves improper validation of input quantities in OSPFv2 packets, which may cause the OSPF process to restart unexpectedly when processing a specially crafted packet from an adjacent OSPF neighbor. This results in an availability impact without affecting confidentiality or integrity. The vulnerability affects EOS versions from 1.0.0 up to and including various subversions up to 4.36.1F. No vendor advisory or patch information is provided, so patch status is unknown.
Potential Impact
The vulnerability causes an unexpected restart of the OSPF process, resulting in a temporary denial of service affecting network availability. There is no impact on confidentiality or integrity. 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, monitoring OSPF stability and limiting adjacency with untrusted neighbors may reduce risk.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- Arista
- Date Reserved
- 2026-08-12T16:39:35.976Z
- Cvss Version
- 3.1
- State
- PUBLISHED
Threat ID: 6aaa621555bf5e2cf54c8cd1
Added to database: 09/16/2026, 09:32:05 UTC
Last enriched: 09/16/2026, 09:47:14 UTC
Last updated: 09/16/2026, 22:11:11 UTC
Views: 11
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