CVE-2026-35386

Affected: OpenBSD OpenSSH

In OpenSSH before 10.3, command execution can occur via shell metacharacters in a username within a command line. This requires a scenario where the username on the command line is untrusted, and also requires a non-default configurations of % in ssh_config.

USN-8222-1 — openssh vulnerabilities

Affected: Ubuntu:22.04:LTS: openssh, Ubuntu:24.04:LTS: openssh, Ubuntu:25.10: openssh, Ubuntu:26.04:LTS: openssh

Christos Papakonstantinou discovered that the OpenSSH scp tool incorrectly handled the legacy scp protocol (-O) option. This could result in certain files being installed setuid or setgid, contrary to expectations. (CVE-2026-35385)

Florian Kohnhäuser discovered that OpenSSH incorrectly handled shell metacharacters in usernames within a command line. When untrusted usernames and non-default configurations using % in ssh_config are being used, an attacker could possibly use this issue to execute arbitrary code. (CVE-2026-35386)

Christos Papakonstantinou discovered that OpenSSH incorrectly handled parsing the PubkeyAcceptedAlgorithms and HostbasedAcceptedAlgorithms options. This could result in unintended ECDSA algorithms being used, contrary to expectations. (CVE-2026-35387)

Michalis Vasileiadis discovered that OpenSSH incorrectly handled proxy-mode multiplexing sessions. This could result in no confirmation being asked, contrary to expectations. (CVE-2026-35388)

Vladimir Tokarev discovered that OpenSSH incorrectly handled certificates with the principal name containing a comma character when using user-trusted CA keys in authorized_keys and an authorized_keys principals="" option that lists more than one principal. This could result in inappropriate principal matching, contrary to expectations. (CVE-2026-35414)

Most recent entries from all

CVE-2026-35386

USN-8222-1 — openssh vulnerabilities