CVE-2026-77185 Apache MINA SSHD: Asynchronous authentication can bypass signature verification
Attackers can bypass signature verification in SSH authentication if the server uses the flawed asynchronous authentication feature.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-77185?
CVE-2026-77185 is a critical authentication bypass vulnerability in Apache MINA SSHD, published on 30 Sep 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
Authentication bypass in sshd-core in Apache MINA SSHD versions 2.0.0 to 2.19.0 and 3.0.0-M1 to 3.0.0-M5 for a certain (presumed rare) way to implement an SSH server.
Apache MINA SSHD is a Java library for client- and server-side SSH. In the server part of the library, a mechanism to perform "asynchronous authentication" exists. A server implemented with Apache MINA SSHD must contain explicit code to make use of this feature. The implementation of this feature was flawed and could potentially lead to skipping checking the signature in public-key or hostbased authentication, or returning a wrong result.
Users are recommended to upgrade to Apache MINA SSHD 2.20.0 or 3.0.0-M6, which fix the logic error and which additionally forbid the use of this "asynchronous authentication" mechanism with the public-key or hostbased authentication schemes: if used, the SSH session will be closed and the server will log an entry indicating that asynchronous authentication may be used only with password or keyboard-interactive authentication.
Weakness: CWE-305
Which versions are affected by CVE-2026-77185?
How do I fix CVE-2026-77185?
Upgrade to a fixed version.
Upgrade, and rotate credentials and sessions that may have been exposed. More about Authentication bypass.
Is CVE-2026-77185 being exploited?
There is no known exploitation of CVE-2026-77185 in the wild and no public exploit code.
Sources
Also known as DEBIAN-CVE-2026-77185, GHSA-v223-2p4c-wp64, UBUNTU-CVE-2026-77185.