# CVE-2025-5351: Libssh: double free vulnerability in libssh key export functions CVE-2025-5351 is fixed in 7 products on 1 platform, first by libssh-4 0.10.6-2ubuntu0.1, released June 24, 2025. It is not reported as exploited. Patch Radar priority: Routine. - Web page: https://patchblox.com/security/cve/CVE-2025-5351 - Priority: Routine - CVSS: 6.5 (Moderate) - EPSS: 0.0063 - CISA KEV: not listed - Exploited (vendor report): no - Publicly disclosed: no - Published: Jun 24, 2025 - Weakness: Double Free - Vendor advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2025-5351 ## Description A flaw was found in the key export functionality of libssh. The issueoccurs in the internal function responsible for converting cryptographickeys into serialized formats. During error handling, a memory structure isfreed but not cleared, leading to a potential double free issue if anadditional failure occurs later in the function. This condition may resultin heap corruption or application instability in low-memory scenarios,posing a risk to system reliability where key export operations areperformed. ## Where it's fixed | Platform | Product | Fixed in | Fix | Released | |---|---|---|---|---| | Linux | libssh Debian 12.15 (bookworm) | 0.10.6-0+deb12u2 | [DEBIAN-CVE-2025-5351](https://patchblox.com/security/data/fix/linux/debian-cve-2025-5351.md) | Jul 4, 2025 | | Linux | libssh Debian 13.5 (trixie) | 0.11.2-1 | [DEBIAN-CVE-2025-5351](https://patchblox.com/security/data/fix/linux/debian-cve-2025-5351.md) | Jul 4, 2025 | | Linux | libssh Debian 14 | 0.11.2-1 | [DEBIAN-CVE-2025-5351](https://patchblox.com/security/data/fix/linux/debian-cve-2025-5351.md) | Jul 4, 2025 | | Linux | libssh RHEL 9 | 0:0.10.4-18.el9 | [RHSA-2026:18683](https://patchblox.com/security/data/fix/linux/rhsa-2026-18683.md) | May 27, 2026 | | Linux | libssh almalinux 9 | 0.10.4-18.el9 | [ALSA-2026:18683](https://patchblox.com/security/data/fix/linux/alsa-2026-18683.md) | May 19, 2026 | | Linux | libssh amzn 2023 | 0.10.6-1.amzn2023.0.2 | [ALAS2023-2025-1155](https://patchblox.com/security/data/fix/linux/alas2023-2025-1155.md) | Aug 18, 2025 | | Linux | libssh ol 9 | 0:0.10.4-18.el9 | [ELSA-2026-18683](https://patchblox.com/security/data/fix/linux/elsa-2026-18683.md) | Jun 12, 2026 | | Linux | libssh rocky 9 | 0:0.10.4-18.el9 | [RLSA-2026:18683](https://patchblox.com/security/data/fix/linux/rlsa-2026-18683.md) | May 28, 2026 | | Linux | libssh-4 Ubuntu 24.04.5 LTS (noble) | 0.10.6-2ubuntu0.1 | [libssh-4 0.10.6-2ubuntu0.1](https://patchblox.com/security/data/fix/linux/ubuntu-noble-libssh-4-0.10.6-2ubuntu0.1.md) | Jun 24, 2025 | | Linux | libssh-4 Ubuntu 24.10 (oracular) | 0.10.6-3ubuntu1.1 | [libssh-4 0.10.6-3ubuntu1.1](https://patchblox.com/security/data/fix/linux/ubuntu-oracular-libssh-4-0.10.6-3ubuntu1.1.md) | Jun 25, 2025 | | Linux | libssh-4 Ubuntu 25.04 (plucky) | 0.11.1-1ubuntu0.1 | [libssh-4 0.11.1-1ubuntu0.1](https://patchblox.com/security/data/fix/linux/ubuntu-plucky-libssh-4-0.11.1-1ubuntu0.1.md) | Jun 25, 2025 | | Linux | libssh-config RHEL 9 | 0:0.10.4-18.el9 | [RHSA-2026:18683](https://patchblox.com/security/data/fix/linux/rhsa-2026-18683.md) | May 27, 2026 | | Linux | libssh-config almalinux 9 | 0.10.4-18.el9 | [ALSA-2026:18683](https://patchblox.com/security/data/fix/linux/alsa-2026-18683.md) | May 19, 2026 | | Linux | libssh-config amzn 2023 | 0.10.6-1.amzn2023.0.2 | [ALAS2023-2025-1155](https://patchblox.com/security/data/fix/linux/alas2023-2025-1155.md) | Aug 18, 2025 | | Linux | libssh-config ol 9 | 0:0.10.4-18.el9 | [ELSA-2026-18683](https://patchblox.com/security/data/fix/linux/elsa-2026-18683.md) | Jun 12, 2026 | | Linux | libssh-debuginfo amzn 2023 | 0.10.6-1.amzn2023.0.2 | [ALAS2023-2025-1155](https://patchblox.com/security/data/fix/linux/alas2023-2025-1155.md) | Aug 18, 2025 | | Linux | libssh-debugsource amzn 2023 | 0.10.6-1.amzn2023.0.2 | [ALAS2023-2025-1155](https://patchblox.com/security/data/fix/linux/alas2023-2025-1155.md) | Aug 18, 2025 | | Linux | libssh-devel RHEL 9 | 0:0.10.4-18.el9 | [RHSA-2026:18683](https://patchblox.com/security/data/fix/linux/rhsa-2026-18683.md) | May 27, 2026 | | Linux | libssh-devel almalinux 9 | 0.10.4-18.el9 | [ALSA-2026:18683](https://patchblox.com/security/data/fix/linux/alsa-2026-18683.md) | May 19, 2026 | | Linux | libssh-devel amzn 2023 | 0.10.6-1.amzn2023.0.2 | [ALAS2023-2025-1155](https://patchblox.com/security/data/fix/linux/alas2023-2025-1155.md) | Aug 18, 2025 | | Linux | libssh-devel ol 9 | 0:0.10.4-18.el9 | [ELSA-2026-18683](https://patchblox.com/security/data/fix/linux/elsa-2026-18683.md) | Jun 12, 2026 | | Linux | libssh-gcrypt-4 Ubuntu 24.04.5 LTS (noble) | 0.10.6-2ubuntu0.1 | [libssh-gcrypt-4 0.10.6-2ubuntu0.1](https://patchblox.com/security/data/fix/linux/ubuntu-noble-libssh-gcrypt-4-0.10.6-2ubuntu0.1.md) | Jun 24, 2025 | | Linux | libssh-gcrypt-4 Ubuntu 24.10 (oracular) | 0.10.6-3ubuntu1.1 | [libssh-gcrypt-4 0.10.6-3ubuntu1.1](https://patchblox.com/security/data/fix/linux/ubuntu-oracular-libssh-gcrypt-4-0.10.6-3ubuntu1.1.md) | Jun 25, 2025 | --- Data as of 2026-11-08T13:06:02Z UTC. 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