CVE-2026-78426 Logout bypass via alternate JWT spelling
Attackers can bypass logout mechanisms in NeuVector by using noncanonical JWT encodings, maintaining access with revoked tokens until expiration.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- A user has to click or open something
- Fix
- None listed
What is CVE-2026-78426?
CVE-2026-78426 is a low-severity authentication bypass vulnerability in SUSE neuvector, published on 17 Sep 2026. Any signed-in user can exploit it over the network, and only if a user opens a file or follows a link.
Official description
The NeuVector JWT verifier accepts noncanonical Base64URL encodings of the same RSA signature field. An attacker holding a valid JWT that has not expired, but was logged out of NeuVector, can continue using the non-expired token with equivalent spelling of the RSA signature field until the token validity expires.
Weakness: CWE-863
Which versions are affected by CVE-2026-78426?
How do I fix CVE-2026-78426?
No fix has been published for CVE-2026-78426 yet. Limit exposure of the affected software until one is available.
Upgrade, and rotate credentials and sessions that may have been exposed. More about Authentication bypass.
Is CVE-2026-78426 being exploited?
There is no known exploitation of CVE-2026-78426 in the wild and no public exploit code.
Sources
Also known as GHSA-wcx5-mq6c-c54j.