Vulnerability · Published Jul 21, 2026 · Assigned by redhat
CVE-2026-59847Libssh: libssh: integrity downgrade via openssl aes-gcm tag verification
Medium 5.9
In plain English
A medium-severity security flaw in Red Hat Enterprise Linux 10 from Red Hat. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.3% (higher than 27% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Severity (CVSS 3.1)5.9Medium
Exploit odds (30 days)0.3%top 73.4% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack toolingNoneno public tooling known
Official description
A flaw was found in libssh. Incorrect AES-GCM finalization checks in builds using the OpenSSL backend can effectively remove integrity protection, allowing an in-path attacker to modify plaintext on the wire without detection.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| AlmaLinux:10 | libssh | 0.12.0-3.el10_2 | ALSA-2026:55855 |
| AlmaLinux:8 | libssh | 0.9.6-17.el8_10 | ALSA-2026:62218 |
| AlmaLinux:9 | libssh | 0.10.4-19.el9_8 | ALSA-2026:62217 |
| AlmaLinux:10 | libssh-config | 0.12.0-3.el10_2 | ALSA-2026:55855 |
| AlmaLinux:8 | libssh-config | 0.9.6-17.el8_10 | ALSA-2026:62218 |
| AlmaLinux:9 | libssh-config | 0.10.4-19.el9_8 | ALSA-2026:62217 |
| AlmaLinux:10 | libssh-devel | 0.12.0-3.el10_2 | ALSA-2026:55855 |
| AlmaLinux:8 | libssh-devel | 0.9.6-17.el8_10 | ALSA-2026:62218 |
| AlmaLinux:9 | libssh-devel | 0.10.4-19.el9_8 | ALSA-2026:62217 |
| Alpine:v3.24 | libssh | 0.12.1-r0 | ALPINE-CVE-2026-59847 |
| Debian:12 | libssh | 0.10.6-0+deb12u3 | DEBIAN-CVE-2026-59847 |
| Debian:13 | libssh | 0.11.5-0+deb13u1 | DEBIAN-CVE-2026-59847 |
| Debian:14 | libssh | 0.12.1-1 | DEBIAN-CVE-2026-59847 |
| Rocky Linux:10 | libssh | 0:0.12.0-3.el10_2 | RLSA-2026:55855 |
| Rocky Linux:8 | libssh | 0:0.9.6-17.el8_10 | RLSA-2026:62218 |
| Rocky Linux:9 | libssh | 0:0.10.4-19.el9_8 | RLSA-2026:62217 |
| Ubuntu:22.04:LTS | libssh | 0.9.6-2ubuntu0.22.04.8 | UBUNTU-CVE-2026-59847 |
| Ubuntu:22.04:LTS | libssh | 0.9.6-2ubuntu0.22.04.8 | USN-8699-1 |
| Ubuntu:24.04:LTS | libssh | 0.10.6-2ubuntu0.5 | UBUNTU-CVE-2026-59847 |
| Ubuntu:24.04:LTS | libssh | 0.10.6-2ubuntu0.5 | USN-8699-1 |
| Ubuntu:26.04:LTS | libssh | 0.11.3-1ubuntu2.1 | USN-8699-1 |
| Ubuntu:26.04:LTS | libssh | 0.11.3-1ubuntu2.1 | UBUNTU-CVE-2026-59847 |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| Red Hat | Red Hat Enterprise Linux 10 | see references |
| Red Hat | Red Hat Enterprise Linux 8 | see references |
| Red Hat | Red Hat Enterprise Linux 8 | see references |
| Red Hat | Red Hat Enterprise Linux 9 | see references |
| Red Hat | Red Hat Enterprise Linux 9 | see references |
| Red Hat | Red Hat Hardened Images | see references |
Weakness: CWE-253, CWE-1310 · Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N
References
- RHSA-2026:42922 vendor-advisory, x_refsource_REDHAT
- RHSA-2026:55855 vendor-advisory, x_refsource_REDHAT
- RHSA-2026:62217 vendor-advisory, x_refsource_REDHAT
- RHSA-2026:62218 vendor-advisory, x_refsource_REDHAT
- https://access.redhat.com/security/cve/CVE-2026-59847 vdb-entry, x_refsource_REDHAT
- RHBZ#2498180 issue-tracking, x_refsource_REDHAT