Description
ssh-agent in OpenSSH before 8.5 has a double free that may be relevant in a few less-common scenarios, such as unconstrained agent-socket access on a legacy operating system, or the forwarding of an agent to an attacker-controlled host.
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | openssh | 1:8.4p1-5 | — |
| Debian 13 | openssh | 1:8.4p1-5 | — |
| Debian 12 | openssh | 1:8.4p1-5 | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 20.04 LTS | openssh | 1:8.2p1-4ubuntu0.2 | USN-4762-1 |
SUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 15 SP3 | openssh +1 | 8.4p1-3.9.1 | SUSE-SU-2021:4153-1 |
Show 1 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLE Micro 5.1 | openssh | 8.4p1-3.9.1 | SUSE-SU-2021:4153-1 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Tumbleweed | openssh | 9.6p1-3.1 | openSUSE-SU-2024:13842-1 |
| openSUSE Leap 15.3 | openssh +1 | 8.4p1-3.9.1 | openSUSE-SU-2021:4153-1 |
Alpine
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Alpine v3.24 | openssh | 8.5_p1-r0 | — |
| Alpine v3.23 | openssh | 8.5_p1-r0 | — |
| Alpine v3.22 | openssh | 8.5_p1-r0 | — |
| Alpine v3.21 | openssh | 8.5_p1-r0 | — |
| Alpine v3.20 | openssh | 8.5_p1-r0 | — |
Show 8 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Alpine v3.19 | openssh | 8.5_p1-r0 | — |
| Alpine v3.18 | openssh | 8.5_p1-r0 | — |
| Alpine v3.17 | openssh | 8.5_p1-r0 | — |
| Alpine v3.16 | openssh | 8.5_p1-r0 | — |
| Alpine v3.15 | openssh | 8.5_p1-r0 | — |
| Alpine v3.14 | openssh | 8.5_p1-r0 | — |
| Alpine v3.13 | openssh | 8.4_p1-r1 | — |
| Alpine v3.12 | openssh | 8.3_p1-r2 | — |
Advisories 10
- SSA-398330 SSA-398330: Vulnerabilities in the additional GNU/Linux subsystem of the SIMATIC S7-1500 CPU 1518(F)-4 PN/DP MFP >= V3.1.0 and < V3.1.5 Siemens ProductCERT · Oct 13, 2026
- USN-4762-1 openssh vulnerability Ubuntu Security Notices (USN) · Feb 10, 2026
- SUSE-SU-2021:4153-1 Security update for openssh SUSE / openSUSE Security Updates · Feb 4, 2026
- openSUSE-SU-2021:4153-1 Security update for openssh SUSE / openSUSE Security Updates · Feb 4, 2026
- openSUSE-SU-2024:13842-1 openssh-9.6p1-3.1 on GA media SUSE / openSUSE Security Updates · Feb 4, 2026
- SCA-2025-0011 Vulnerabilities affecting Endress+Hauser SSG-E210GC SICK PSIRT · Oct 2, 2025
- ICSA-23-348-10 Siemens SIMATIC S7-1500 CISA ICS & IT advisories · Aug 12, 2025
- SCA-2025-0009 Vulnerabilities affecting SICK TDC-E210GC SICK PSIRT · Aug 1, 2025
- WID-SEC-2024-1082 Juniper JUNOS: Mehrere Schwachstellen BSI CERT-Bund (WID) · May 9, 2024
- WID-SEC-2023-0997 OpenSSH: Schwachstelle ermöglicht Codeausführung BSI CERT-Bund (WID) · May 7, 2024
References
- https://www.openssh.com/security.html
- https://www.openwall.com/lists/oss-security/2021/03/03/1
- https://github.com/openssh/openssh-portable/commit/e04fd6dde16de1cdc5a4d9946397ff60d96568db
- https://www.openssh.com/txt/release-8.5
- FEDORA-2021-f68a5a75ba vendor-advisory
- GLSA-202105-35 vendor-advisory
- FEDORA-2021-1d3698089d vendor-advisory
- https://www.oracle.com//security-alerts/cpujul2021.html
- https://security.netapp.com/advisory/ntap-20210416-0002/