CVE-2026-19641 Denial of service in EOS
A crafted password can exhaust authentication resources on Arista EOS devices, preventing legitimate users from logging in.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-19641?
CVE-2026-19641 is a medium-severity denial of service vulnerability in Arista Networks EOS, published on 15 Sep 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
On affected platforms running Arista EOS with password authentication configured, a specially crafted password can create orphan authentication sessions. Repeated exploitation of this issue can exhaust available authentication resources, resulting in legitimate users being unable to log in to the device.
This issue was discovered internally by Arista, and the company is not aware of any malicious exploitation of this vulnerability in customer networks.
Weakness: CWE-116
Which versions are affected by CVE-2026-19641?
How do I fix CVE-2026-19641?
No fix has been published for CVE-2026-19641 yet. Limit exposure of the affected software until one is available.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2026-19641 being exploited?
There is no known exploitation of CVE-2026-19641 in the wild and no public exploit code.
Sources
Also known as GHSA-rxmx-2jm2-79fq.