CVE-2026-73435: Arista Networks EOS · Insufficient Verification of Data Authenticity
Affects Arista Networks EOSSource CVE Database V5
Not known to be exploited · CVSS 8.2 High : upgrade to 4.33.0F soon.
Data as of 31 Oct 2026, 20:20 UTC
- EPSS
- 0.1% chance of exploitation in 30 days – higher than 8% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 4.33.0F
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:C/C:N/I:L/A:HExploitation evidence
Disclosed: evidence found.
CVE published 16 Sep 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: 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 31 Oct 2026.
What to do
Upgrade Arista Networks EOS to 4.33.0F.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| Arista NetworksEOS | Affected
| Fixed in
|
AI-suggested
If you cannot patch yet, network administrators should consider network segmentation or OSPF authentication configuration reviews to limit exposure from unauthenticated attackers on the same broadcast segment.
Description
On affected platforms running Arista EOS with Open Shortest Path First version 2 (OSPFv2) configured, a specially crafted OSPFv2 packet from an unauthenticated attacker on the same broadcast segment, with OSPFv2 authentication configured can cause adjacency flapping and packet loss. The disruption can affect routing across the broader OSPF domain.