CVE-2024-39894

OpenSSH 9.5 through 9.7 before 9.8 sometimes allows timing attacks against echo-off password entry (e.g., for su and Sudo) because of an ObscureKeystrokeTiming logic error. Similarly, other timing attacks against keystroke entry could occur.

Weakness

The product checks the state of a resource before using that resource, but the resource’s state can change between the check and the use in a way that invalidates the results of the check. This can cause the product to perform invalid actions when the resource is in an unexpected state.

Affected Software

Potential Mitigations

Related Attack Patterns

• https://cwe.mitre.org/data/definitions/27.html
• https://cwe.mitre.org/data/definitions/29.html

References

• http://www.openwall.com/lists/oss-security/2024/07/03/6
• http://www.openwall.com/lists/oss-security/2024/07/23/4
• http://www.openwall.com/lists/oss-security/2024/07/23/6
• http://www.openwall.com/lists/oss-security/2024/07/28/3
• https://crzphil.github.io/posts/ssh-obfuscation-bypass/
• https://lists.mindrot.org/pipermail/openssh-unix-announce/2024-July/000158.html
• https://news.ycombinator.com/item?id=41508530
• https://security.netapp.com/advisory/ntap-20240712-0004/
• https://www.openssh.com/txt/release-9.8
• https://www.openwall.com/lists/oss-security/2024/07/02/1