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TI-2026-53911 Aliases CVE-2026-77190GHSA-738x-gmrv-v9j5

Improper input validation in Arista EOS

Priority LOW 27CWE-20Published · Updated

Key facts

Attack vector
Adjacent network
Privileges required
None
User interaction
None
Attack complexity
Low
Attack requirements
Present
Impact type
—
Confidentiality · integrity · availability
None · None · High
Fix status
No fix listed

Attack profile from CVSS 4.0 · CNA. Fix status from CNA.

Summary

On affected platforms running Arista EOS, an unauthenticated attacker who is network-adjacent to the switch and able to connect to a device with PIM Sparse Mode and MLAG configured, can send malformed messages that cause the Pimsm agent to terminate unexpectedly. The Pimsm agent is automatically restarted, but repeated attacks can cause the agent to restart continuously, resulting in a sustained denial of service.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00281 20th percentileScored 2026-11-07
Fix No fix listed No fixed version in the sources yet

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
AristaEOS4.36.0F – 4.36.1F; 4.35.0F – 4.35.5M; 4.34.2F – 4.34.7M—No fix listedCNA
  • EOS VendorArista Affected 4.36.0F – 4.36.1F; 4.35.0F – 4.35.5M; 4.34.2F – 4.34.7M Fixed in — No fix listed CNA

Remediation

No fixed version listed by the sources yet.

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-77190
  2. 2026-10-03 Alias added: GHSA-738x-gmrv-v9j5

References

Advisory 1

  • TI-2026-79524 Privilege escalation in Arista VeloCloud Orchestrator on-premises KEVCVSS 4.0CRITICAL 9.4
  • TI-2026-63212 Improper input validation in Arista VeloCloud Orchestrator On-Prem KEVCVSS 4.0CRITICAL 9.5
  • TI-2026-13992 VeloCloud Orchestrator OS Command Injection KEVCVSS 4.0CRITICAL 10.0
  • TI-2014-05975 GNU Bash through 4.3 bash43-025 processes trailing strings after certain malformed… KEVCVSS 3.1CRITICAL 9.8
  • TI-2014-05157 GNU Bash through 4.3 processes trailing strings after function definitions in the values… KEVCVSS 3.1CRITICAL 9.8
  • TI-2026-23989 crypto: algif_aead - Revert to operating out-of-place KEVCVSS 3.1HIGH 7.8
See all 216 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences