Quick answers
- Is CVE-2026-121293 exploited in the wild?
- No. Junglewise Threat Intelligence has no report of CVE-2026-121293 being exploited in the wild.
- How severe is CVE-2026-121293?
- Medium severity, with a CVSS score of 4.4, published 10 November 2026.
- Which products and versions are affected?
- Arista cEOS-lab affected versions same as EOS; Arista CloudEOS affected versions same as EOS; Arista Eos 4.36.2F and below (4.36.x), 4.35.6M and below (4.35.x), 4.34.8M and below (4.34.x), 4.33.10M and below (4.33.x), all 4.32.x, all End of Support trains; Arista vEOS-lab affected versions same as EOS.
- Is there a fix for CVE-2026-121293?
- No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.
- How is CVE-2026-121293 attacked?
- It is attacked over the network, in an operating system.
- Am I affected by CVE-2026-121293?
- Check whether you run Arista cEOS-lab, Arista CloudEOS, Arista Eos or one of the others listed at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.
Technical details
A null pointer dereference in the EOS BGP process occurs when a crafted BGP message is received over an established session with the Dynamic Path Selection (DPS) address family negotiated. The vulnerability requires the attacker to control a BGP peer and have an active DPS-negotiated session; exploitation causes the BGP process to crash (SIGSEGV or SIGABRT), resetting all BGP sessions and disrupting routing. Patched versions are available.
Affected products
- Arista EOS 4.36.2F and below (4.36.x), 4.35.6M and below (4.35.x), 4.34.8M and below (4.34.x), 4.33.10M and below (4.33.x), all 4.32.x, all End of Support trains
- Arista CloudEOS affected versions same as EOS
- Arista cEOS-lab affected versions same as EOS
- Arista vEOS-lab affected versions same as EOS
Timeline
- 2026-11-10: disclosed