Portable OpenSSH 10.6p2 Released With Security Workaround and Bug Fixes

Portable OpenSSH 10.6p2 was released on November 5, 2026, and will be available from the project's mirrors. The release contains a critical security workaround for a password authentication bypass on some Linux systems, along with bugfixes and portability fixes. OpenSSH is a complete SSH protocol 2.0 implementation that includes sftp client and server support.

Security workaround

This release contains a critical security workaround that affects Linux systems that use musl libc and PAM disabled. It avoids a password authentication bypass exploitable through sshd(8) on some Linux systems built and run with PAM support disabled. The OpenSSH team considers the root cause to be outside sshd, but says it is exploitable via sshd and can be avoided there. The bug was reported by Özgün Kültekin of Wakefield (wakefield.co).

Bugfixes and portability

sshd(8) and ssh(1) now enable the post-quantum hybris signature scheme ssh-mldsa44-ed25519 as an allowed CA signature algorithm. ssh(1) and sshd(8) also fix a CPU spin of under one second when ChannelTimeout was in use. The release fixes compilation on older platforms that set SKIP_PRIVDROP, improves detection of Azerbaijani locales, and fixes creation of agent sockets on platforms without the openat(2) syscall. It also fixes strange behavior in ssh(1), ssh-add(1), and ssh-keygen(1) when SIGINT or SIGQUIT is received while reading a passphrase, and allows restart_syscall(2) in the seccomp sandbox (bz4036).

Deprecation notices

scp(1) begins deprecating the -R flag used for remote-to-remote copy by executing scp on a remote host. The option remains functional from OpenSSH 10.6 but emits a deprecation warning to standard error; in a future release it will be ignored, leaving the default remote-to-remote copy behavior of copying via the host running scp. Separately, support for platforms that do not allow file descriptor passing and also require root privilege for PTY allocation will be removed in a future release. Known affected platforms include SCO OpenServer 5 and QNX 6, and the deprecation may be avoided if affected platform communities help build alternatives such as avoiding the need for root in PTY allocation.

AI reports, release cadence, community, and checksums

The OpenSSH team says it has received many security bug reports recently, many from AI models or made with AI assistance. Many AI reports are determined not to have security impact in a realistic threat model, but the team welcomes them, especially with human triage, analysis, test cases, and proposed fixes. The team has seen security bugs identified by AI tools later independently discovered by a different researcher, suggesting adversaries who do not report bugs to open source projects may also discover them. For now, the team will make more frequent releases to get bugfixes to users more quickly rather than batching them until the next planned release. The team thanked the community, especially contributors of code or patches, bug reporters, snapshot testers, and donors; more information on donations is available from the project. The release lists SHA1 (openssh-10.6p2.tar.gz) = c91a0b7860c80f29db874044af4d1a6f906231d9 and SHA256 (openssh-10.6p2.tar.gz) = muRIcgkM8vBrPPn/FH5/FvMJZxNAdj7S+ZJIOYrinVs=. The SHA256 checksum is base64 encoded rather than hexadecimal. The PGP key used to sign releases is available from mirror sites. Security bugs should be reported directly to [email protected].

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