ALAS2023-2025-865


Amazon Linux 2023 Security Advisory: ALAS2023-2025-865
Advisory Released Date: 2025-03-06
Advisory Updated Date: 2025-03-06
Severity: Medium

Issue Overview:

A vulnerability was found in OpenSSH when the VerifyHostKeyDNS option is enabled. A machine-in-the-middle attack can be performed by a malicious machine impersonating a legit server. This issue occurs due to how OpenSSH mishandles error codes in specific conditions when verifying the host key. For an attack to be considered successful, the attacker needs to manage to exhaust the client's memory resource first, turning the attack complexity high. (CVE-2025-26465)


Affected Packages:

openssh


Issue Correction:
Run dnf update openssh --releasever 2023.6.20250303 to update your system.

New Packages:
aarch64:
    openssh-clients-debuginfo-8.7p1-8.amzn2023.0.14.aarch64
    pam_ssh_agent_auth-debuginfo-0.10.4-4.8.amzn2023.0.14.aarch64
    openssh-debuginfo-8.7p1-8.amzn2023.0.14.aarch64
    openssh-keycat-debuginfo-8.7p1-8.amzn2023.0.14.aarch64
    openssh-server-8.7p1-8.amzn2023.0.14.aarch64
    openssh-server-debuginfo-8.7p1-8.amzn2023.0.14.aarch64
    openssh-debugsource-8.7p1-8.amzn2023.0.14.aarch64
    openssh-8.7p1-8.amzn2023.0.14.aarch64
    openssh-keycat-8.7p1-8.amzn2023.0.14.aarch64
    pam_ssh_agent_auth-0.10.4-4.8.amzn2023.0.14.aarch64
    openssh-clients-8.7p1-8.amzn2023.0.14.aarch64

src:
    openssh-8.7p1-8.amzn2023.0.14.src

x86_64:
    openssh-clients-debuginfo-8.7p1-8.amzn2023.0.14.x86_64
    openssh-keycat-8.7p1-8.amzn2023.0.14.x86_64
    pam_ssh_agent_auth-debuginfo-0.10.4-4.8.amzn2023.0.14.x86_64
    openssh-server-debuginfo-8.7p1-8.amzn2023.0.14.x86_64
    openssh-8.7p1-8.amzn2023.0.14.x86_64
    pam_ssh_agent_auth-0.10.4-4.8.amzn2023.0.14.x86_64
    openssh-keycat-debuginfo-8.7p1-8.amzn2023.0.14.x86_64
    openssh-debuginfo-8.7p1-8.amzn2023.0.14.x86_64
    openssh-server-8.7p1-8.amzn2023.0.14.x86_64
    openssh-clients-8.7p1-8.amzn2023.0.14.x86_64
    openssh-debugsource-8.7p1-8.amzn2023.0.14.x86_64