Description
A NULL pointer dereference was found In libssh during re-keying with algorithm guessing. This issue may allow an authenticated client to cause a denial of service.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| — | libssh | libssh-2 | — |
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 | libssh | 0.10.5-1 | — |
| Debian 13 | libssh | 0.10.5-1 | — |
| Debian 12 | libssh | 0.10.5-1 | — |
| Debian 11 | libssh | 0.9.7-0+deb11u1 | DSA-5409-1 |
| Debian 10 | libssh | 0.8.7-1+deb10u2 | DLA-3437-1 |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 22.04 LTS | libssh | 0.9.6-2ubuntu0.22.04.1 | USN-6138-1 |
| Ubuntu 20.04 LTS | libssh | 0.9.3-2ubuntu2.3 | USN-6138-1 |
Show 2 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu Pro 18.04 LTS | libssh | No fix yet | — |
| Ubuntu Pro 16.04 LTS | libssh | No fix yet | — |
Red Hat
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| RHEL 9 | libssh +2 | 0.10.4-11.el9 | RHSA-2023:6643 |
| RHEL 8 | libssh +2 | 0.9.6-10.el8_8 | RHSA-2023:3839 |
Show 1 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| RHEL 8.6 EUS | libssh +2 | 0.9.6-4.el8_6 | RHSA-2024:0538 |
AlmaLinux
Errata ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| AlmaLinux 9 | libssh +2 | 0.10.4-11.el9 | ALSA-2023:6643 |
| AlmaLinux 8 | libssh +2 | 0.9.6-10.el8_8 | ALSA-2023:3839 |
Rocky Linux
Errata ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Rocky Linux 8 | libssh | 0.9.6-10.el8_8 | RLSA-2023:3839 |
SUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 15 SP5 | libssh | 0.9.8-150400.3.3.1 | SUSE-SU-2024:0140-1 |
| SLES 15 SP4 | libssh | 0.9.8-150400.3.3.1 | SUSE-SU-2024:0140-1 |
| SLES 15 SP3 | libssh | 0.9.8-150200.13.3.1 | SUSE-SU-2024:0525-1 |
| SLES 15 SP2 | libssh | 0.9.8-150200.13.3.1 | SUSE-SU-2024:0525-1 |
| SLES 12 SP5 | libssh | 0.9.8-3.12.2 | SUSE-SU-2024:0539-1 |
Show 16 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES for SAP 15 SP4 | libssh | 0.9.8-150400.3.3.1 | SUSE-SU-2024:0140-1 |
| SLES for SAP 15 SP3 | libssh | 0.9.8-150200.13.3.1 | SUSE-SU-2024:0525-1 |
| SLES for SAP 15 SP2 | libssh | 0.9.8-150200.13.3.1 | SUSE-SU-2024:0525-1 |
| SLES for SAP 12 SP5 | libssh | 0.9.8-3.12.2 | SUSE-SU-2024:0539-1 |
| SLE Real Time 15 SP4 | libssh | 0.9.8-150400.3.3.1 | SUSE-SU-2024:0140-1 |
| SLE Micro 5.5 | libssh | 0.9.8-150400.3.3.1 | SUSE-SU-2024:0140-1 |
| SLE Micro 5.4 | libssh | 0.9.8-150400.3.3.1 | SUSE-SU-2024:0140-1 |
| SLE Micro 5.3 | libssh | 0.9.8-150400.3.3.1 | SUSE-SU-2024:0140-1 |
| SLE Micro 5.2 | libssh | 0.9.8-150200.13.3.1 | SUSE-SU-2024:0525-1 |
| SLE Micro 5.1 | libssh | 0.9.8-150200.13.3.1 | SUSE-SU-2024:0525-1 |
| SLE HPC 15 SP4 | libssh | 0.9.8-150400.3.3.1 | SUSE-SU-2024:0140-1 |
| SLE HPC 15 SP3 | libssh | 0.9.8-150200.13.3.1 | SUSE-SU-2024:0525-1 |
| SLE HPC 15 SP2 | libssh | 0.9.8-150200.13.3.1 | SUSE-SU-2024:0525-1 |
| SUSE Manager Server 4.3 | libssh | 0.9.8-150400.3.3.1 | SUSE-SU-2024:0140-1 |
| SUSE Manager Proxy 4.3 | libssh | 0.9.8-150400.3.3.1 | SUSE-SU-2024:0140-1 |
| SUSE Enterprise Storage 7.1 | libssh | 0.9.8-150200.13.3.1 | SUSE-SU-2024:0525-1 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Tumbleweed | libssh | 0.10.5-1.1 | openSUSE-SU-2024:12914-1 |
| openSUSE Leap 15.5 | libssh | 0.9.8-150400.3.3.1 | SUSE-SU-2024:0140-1 |
Show 2 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Leap Micro 5.4 | libssh | 0.9.8-150400.3.3.1 | SUSE-SU-2024:0140-1 |
| openSUSE Leap Micro 5.3 | libssh | 0.9.8-150400.3.3.1 | SUSE-SU-2024:0140-1 |
Amazon Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Amazon Linux 2023 | libssh +2 | 0.10.5-1.amzn2023.0.1 | ALAS2023-2023-186 |
Oracle Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Oracle Linux 9 | libssh +2 | 0.10.4-11.el9 | ELSA-2023-6643 |
| Oracle Linux 8 | libssh +2 | 0.9.6-10.el8_8 | ELSA-2023-3839 |
Advisories 19
- ALSA-2023:6643 Moderate: libssh security update AlmaLinux Security Advisories · Oct 29, 2026
- ALSA-2023:3839 Moderate: libssh security update AlmaLinux Security Advisories · Oct 29, 2026
- RHSA-2024:0538 Red Hat Security Advisory: libssh security update Red Hat Security Advisories (RHSA) · Oct 17, 2026
- RHSA-2023:6643 Red Hat Security Advisory: libssh security update Red Hat Security Advisories (RHSA) · Jun 30, 2026
- RHSA-2023:3839 Red Hat Security Advisory: libssh security update Red Hat Security Advisories (RHSA) · Jun 30, 2026
- USN-6138-1 libssh vulnerabilities Ubuntu Security Notices (USN) · Apr 22, 2026
- DSA-5409-1 libssh - security update Debian Security (DSA / DLA) · Mar 9, 2026
- DLA-3437-1 libssh - security update Debian Security (DSA / DLA) · Mar 9, 2026
- RLSA-2023:3839 Moderate: libssh security update Rocky Linux Security Advisories · Feb 5, 2026
- SUSE-SU-2024:0140-1 Security update for libssh SUSE / openSUSE Security Updates · Feb 4, 2026
- openSUSE-SU-2024:12914-1 libssh-config-0.10.5-1.1 on GA media SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2024:0539-1 Security update for libssh SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2024:0525-1 Security update for libssh SUSE / openSUSE Security Updates · Feb 4, 2026
- WID-SEC-2023-1159 libssh: Mehrere Schwachstellen ermöglichen Umgehung von Sicherheitsvorkehrungen BSI CERT-Bund (WID) · Jan 25, 2026
- WID-SEC-2024-3377 Dell PowerProtect Data Domain: Mehrere Schwachstellen BSI CERT-Bund (WID) · Oct 12, 2025
- ELSA-2023-6643 Moderate: libssh security update (Oracle Linux 9) Oracle Linux Security Advisories (ELSA) · Nov 11, 2023
- WID-SEC-2023-2112 IBM Spectrum Protect: Mehrere Schwachstellen BSI CERT-Bund (WID) · Aug 22, 2023
- ELSA-2023-3839 Moderate: libssh security update (Oracle Linux 8) Oracle Linux Security Advisories (ELSA) · Jun 29, 2023
- ALAS2023-2023-186 Moderate: libssh security update (Amazon Linux 2023) Amazon Linux Security Center (ALAS) · Jun 7, 2023
References
- https://access.redhat.com/security/cve/CVE-2023-1667
- https://bugzilla.redhat.com/show_bug.cgi?id=2182199
- http://www.libssh.org/security/advisories/CVE-2023-1667.txt
- FEDORA-2023-5fa5ca2043 vendor-advisory
- [debian-lts-announce] 20230529 [SECURITY] [DLA 3437-1] libssh security update mailing-list
- GLSA-202312-05 vendor-advisory