CVE-2026-77185 Apache MINA SSHD 认证绕过漏洞
影响攻击者可绕过公钥或主机认证，未授权访问 SSH 服务
Apache MINA SSHD 是 Java 的 SSH 客户端与服务端库，其服务端提供"异步认证"机制。该机制实现存在逻辑缺陷，在特定实现方式下可能跳过公钥或主机认证的签名校验，或返回错误结果，从而导致认证绕过。
影响范围
影响 Apache MINA SSHD 2.0.0 至 2.19.0，以及 3.0.0-M1 至 3.0.0-M5。仅当服务端显式使用异步认证机制时才受影响。
漏洞详情
漏洞类型为认证绕过，成因是异步认证逻辑实现错误，在公钥或主机认证场景下未正确校验签名或返回错误结果。利用需服务端代码显式启用该异步认证特性，属于特定（据称较罕见）的实现方式。攻击者可能借此绕过身份验证获得访问权限。
利用条件与风险
利用前提是目标 SSH 服务端使用 Apache MINA SSHD 并显式启用了异步认证机制，且采用公钥或主机认证。满足条件时风险极高，可导致未授权访问。
修复建议
官方建议升级至 Apache MINA SSHD 2.20.0 或 3.0.0-M6，新版本修复逻辑错误并禁止在公钥或主机认证中使用异步认证（若使用则关闭会话并记录日志）。临时缓解措施为不使用异步认证机制，或改用密码/键盘交互认证。
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.