Improper validation of integrity check value in libssh - CVE-2026-59847

CSH
CYBERSECURITY HELP
Sign In REGISTER
 
Main Vulnerability Database Vulnerabilities #VU139530

Improper validation of integrity check value in libssh - CVE-2026-59847

Published: July 27, 2026


Vulnerability identifier: #VU139530
CSH Severity: Medium
CVSS v4: 8.3 [CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:H/VA:L/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-59847
CWE-ID: CWE-354
Exploitation vector: Remote access
Exploit availability: No public exploit available

Vulnerability details

The vulnerability allows a remote attacker to modify plaintext transmitted over the connection without being detected.

The vulnerability exists due to improper integrity check in the OpenSSL AES-GCM backend when processing encrypted SSH traffic. A remote attacker can flip bits in packets in transit to modify plaintext transmitted over the connection without being detected.

Only OpenSSL-based server and client configurations using the affected AES-GCM ciphers are vulnerable. Successful exploitation requires knowledge of the expected plaintext format of the packets.


Affected software

libssh
SUSE Linux Enterprise Server 15 SP5
SUSE Linux Enterprise Server 15 SP4
SUSE Linux Enterprise Server 15 SP6
SUSE Linux Enterprise Server for SAP Applications 15
SUSE Linux Enterprise Server 15
SUSE Linux Enterprise High Performance Computing LTSS 15
SUSE Linux Enterprise High Performance Computing ESPOS 15
SUSE Linux Enterprise High Performance Computing 15
SUSE Linux Enterprise Real Time 15
SUSE Linux Enterprise Desktop 15
SUSE Linux Enterprise Micro
SUSE Linux Enterprise Micro for Rancher
Red Hat Enterprise Linux for x86_64
Red Hat Enterprise Linux for ARM 64
Red Hat Enterprise Linux for IBM z Systems
Red Hat Enterprise Linux for Power, little endian
Basesystem Module
openSUSE Leap
openEuler
Ubuntu
Anolis OS
libssh
libssh-debuginfo
libssh-debugsource
libssh-devel
libssh-help
libssh (Ubuntu package)
libssh4-32bit
libssh4-64bit
libssh4-64bit-debuginfo
libssh4-32bit-debuginfo
libssh4
libssh4-debuginfo
libssh-config
libssh (Red Hat package)
libssh-doc

How to mitigate CVE-2026-59847

Install security update from vendor's website.

libssh - addressed in versions 0.11.5, 0.12.1
libssh - addressed in versions 0.9.4-21, 0.9.6-21, 0.10.5-15
libssh-debuginfo - addressed in versions 0.9.4-21, 0.9.6-21, 0.10.5-15
libssh-debugsource - addressed in versions 0.9.4-21, 0.9.6-21, 0.10.5-15
libssh-devel - addressed in versions 0.9.4-21, 0.9.6-21, 0.10.5-15
libssh-help - addressed in versions 0.9.4-21, 0.9.6-21, 0.10.5-15
libssh (Ubuntu package) - addressed in versions 0.9.6-2ubuntu0.22.04.8, 0.10.6-2ubuntu0.5, 0.11.3-1ubuntu2.1
libssh4-32bit - addressed in versions 0.9.8-150400.3.20.1, 0.9.8-150600.11.15.1
libssh4-64bit - addressed in versions 0.9.8-150400.3.20.1, 0.9.8-150600.11.15.1
libssh4-64bit-debuginfo - addressed in versions 0.9.8-150400.3.20.1, 0.9.8-150600.11.15.1
libssh4-32bit-debuginfo - addressed in versions 0.9.8-150400.3.20.1, 0.9.8-150600.11.15.1
libssh4 - addressed in versions 0.9.8-150400.3.20.1, 0.9.8-150600.11.15.1
libssh4-debuginfo - addressed in versions 0.9.8-150400.3.20.1, 0.9.8-150600.11.15.1
libssh-debugsource - addressed in versions 0.9.8-150400.3.20.1, 0.9.8-150600.11.15.1
libssh-config - addressed in versions 0.9.8-150400.3.20.1, 0.9.8-150600.11.15.1
libssh-devel - addressed in versions 0.9.8-150400.3.20.1, 0.9.8-150600.11.15.1
libssh (Red Hat package) - addressed in versions 0.10.4-19.el9_8, 0.12.0-3.el10_2
libssh - update to 0.10.5-17
libssh-devel - update to 0.10.5-17
libssh-config - update to 0.10.5-17
libssh-doc - update to 0.10.5-17

External References

Related Security Bulletins