CVE-2026-77190
Security Advisory 0177
No known exploitation. EPSS puts it in the 18th percentile. A vendor fix is available.
What to do
The vendor has published a fix. Version details are below where the sources state them.
What it is
From the CVE record
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.
In plain language
No plain-language summary for this CVE yet.
Exploitation
Where each signal puts this CVE on the scale from published to confirmed exploited.
- CISA KEV
Not in the catalog. CISA has not confirmed exploitation.
- Public exploits
No public exploit or proof of concept found in the sources we track.
- EPSS
0.3% chance of exploitation activity in the next 30 days, which ranks it in the 18th percentile of scored CVEs.
Exploit Prediction Scoring System, FIRST.org. A probability, not a confirmation.
Lifecycle
12 events over 0 days, from the signal feeds we watch.
- Patch availablepatch available, patch available, workaround available, workaround available, workaround available, published, weakness classified, att&ck mapped, record updated, record updated, record updated
Affected products
Technical detail
CVSS 3.1 vector
Open in the CVSS calculatorCVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Scored 6.5 by NVD.
How it is reached
- Attack Vector AdjacentRequires access to the local network (e.g. same Wi-Fi, Bluetooth)
- Attack Complexity LowNo special conditions — the attack can be reliably reproduced
- Privileges Required NoneNo authentication required — anyone can exploit this
- User Interaction NoneNo user interaction needed — fully automated exploitation
Scope
- Scope UnchangedImpact is limited to the vulnerable component itself
Impact if exploited
- Confidentiality NoneNo confidentiality impact
- Integrity NoneNo integrity impact
- Availability HighTotal denial of service — the component is completely unavailable
Weaknesses
ATT&CK techniques
Mapped from the weaknesses above (CWE to ATT&CK), not observed in attacks.
- Initial AccessT1190Exploit Public-Facing Applicationlow confidence
Sources
References in the record
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