CVE-2023-25136
Description
OpenSSH server (sshd) 9.1 introduced a double-free vulnerability during options.kex_algorithms handling. This is fixed in OpenSSH 9.2. The double free can be leveraged, by an unauthenticated remote attacker in the default configuration, to jump to any location in the sshd address space. One third-party report states "remote code execution is theoretically possible."
Predictions
Heuristic predictions, AS-IS, for prioritization only.
Mitigations
No mitigations published for this CVE yet.
The vendor-content worker queues fetches as references arrive (check back in a few minutes). Or — if you've already worked around this in production — publish your fix to the community-verified tier.
✚ Propose a mitigation on Community → Mitigations published via the community go through AI scoring + 2 human reviewers + 7-day silent objection window before landing here withsource_tier=community-verified.
OS impact
| OS | Version | Status | Fixed in |
|---|---|---|---|
| arch | fixed | 9.2p1-1 | |
| rhel | 9 | fixed | |
| debian | bookworm | fixed | 1:9.2p1-1 |
| debian | bullseye | fixed | 0 |
| debian | forky | fixed | 1:9.2p1-1 |
| debian | sid | fixed | 1:9.2p1-1 |
| debian | trixie | fixed | 1:9.2p1-1 |
| fedora | 37 | affected | |
| fedora | 38 | affected | |
Application impact
| Vendor | Product | Versions | Fixed |
|---|---|---|---|
| openbsd | openssh | 9.1 | |
| netapp | ontap_select_deploy_administration_utility | - | |
| netapp | a250 | - | |
| netapp | 500f | - | |
| netapp | c250 | - | |
References
- https://access.redhat.com/errata/RHSA-2023:2645
- https://security-tracker.debian.org/tracker/CVE-2023-25136
- https://bugzilla.redhat.com/2167636
- https://errata.almalinux.org/9/ALSA-2023-2645.html
- http://www.openwall.com/lists/oss-security/2023/02/13/1
- http://www.openwall.com/lists/oss-security/2023/02/22/1
- http://www.openwall.com/lists/oss-security/2023/02/22/2
- http://www.openwall.com/lists/oss-security/2023/02/23/3
- http://www.openwall.com/lists/oss-security/2023/03/06/1
- http://www.openwall.com/lists/oss-security/2023/03/09/2
- https://bugzilla.mindrot.org/show_bug.cgi?id=3522
- https://ftp.openbsd.org/pub/OpenBSD/patches/7.2/common/017_sshd.patch.sig
- https://github.com/openssh/openssh-portable/commit/486c4dc3b83b4b67d663fb0fa62bc24138ec3946
- https://jfrog.com/blog/openssh-pre-auth-double-free-cve-2023-25136-writeup-and-proof-of-concept/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/JGAUIXJ3TEKCRKVWFQ6GDAGQFTIIGQQP/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/R7LKQDFZWKYHQ65TBSH2X2HJQ4V2THS3/
- https://news.ycombinator.com/item?id=34711565
- https://security.gentoo.org/glsa/202307-01
- https://security.netapp.com/advisory/ntap-20230309-0003/
- https://www.openwall.com/lists/oss-security/2023/02/02/2
CWEs
CWE-415
Community-verified mitigations for this CVE will appear above when contributors publish them.
Verify integrity in audit chain (admin only). AS-IS.