Apache MINA SSHD: authentication bypass
High8.1CVE-2026-93994 · Published Sep 30, 2026
Apache MINA SSHD is a Java library for client-side and server-side SSH. SSH servers can be configured to require multi-authentication schemes, for instance two different public keys, not just one. In OpenSSH, this would be done by setting in sshd_config AuthenticationMethods "publickey,publickey". Apache MINA SSHD provides an equivalent configuration mechanism. In Apache MINA SSHD versions up to 2.19.0 and 3.0.0-M1 to 3.0.0-M5 the server code in component sshd-core does not enforce that the two public keys presented are different. A user can thus successfully authenticate with only one of the two key pairs required by presenting this single key twice. This is a partial authentication bypass. Users are recommended to upgrade to version 2.20.0 or 3.0.0-M6, which fix this issue.
Affected versions
| Package | Affected | Fixed in |
|---|---|---|
| Apache MINA SSHD Product | < 2.20.0 | 2.20.0 |
| >= 3.0.0-M1, < 3.0.0-M6 | 3.0.0-M6 |
Details and references
- CVSS 3.1
- CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N
- Severity from
- the vendor (its own CVE record or advisory)
- Weakness
- CWE-304
More Apache Software Foundation advisories
All Apache Software Foundation| Date | Advisory | Severity | Fixed in |
|---|---|---|---|
| Sep 30 | Apache WSS4J: integer overflow | High7.5 | 4.0.2+2 more |
| Sep 30 | Apache WSS4J: insufficient authenticity check | Critical9.1 | 4.0.2+2 more |
| Sep 30 | Apache WSS4J: protection mechanism failure | High7.5 | 4.0.2+2 more |
| Sep 30 | Apache WSS4J: authentication bypass by spoofing | Medium4.8 | 4.0.2+2 more |
| Sep 30 | Apache WSS4J: expression injection | Critical9.1 | 4.0.2+2 more |
| Sep 30 | Apache WSS4J: authentication bypass | Critical9.8 | 4.0.2+2 more |