Out-of-bounds read in libssh2 - CVE-2025-15661

CSH
CYBERSECURITY HELP
Sign In REGISTER
 
Main Vulnerability Database Vulnerabilities #VU136047

Out-of-bounds read in libssh2 - CVE-2025-15661

Published: July 1, 2026


Vulnerability identifier: #VU136047
CSH Severity: Medium
CVSS v4: 8.8 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:L/SC:N/SI:N/SA:N]
CVE-ID: CVE-2025-15661
CWE-ID: CWE-125
Exploitation vector: Remote access
Exploit availability: No public exploit available

Vulnerability details

The vulnerability allows a remote attacker to gain access to potentially sensitive information.

The vulnerability exists due to a boundary condition within the sftp_symlink() function in src/sftp.c. A malicious SSH server or a man-in-the-middle attacker can disclose heap memory contents or cause application crash by sending a crafted SSH_FXP_NAME response.


Affected software

libssh2
Gentoo Linux
Debian Linux
openEuler
Anolis OS
Ubuntu
libssh2-1t64 (Ubuntu package)
libssh2-debuginfo
libssh2-debugsource
libssh2-devel
libssh2-help
libssh2
libssh2-docs
net-libs/libssh2
libssh2 (Debian package)

How to mitigate CVE-2025-15661

Install updates from vendor's repository.

libssh2-1t64 (Ubuntu package) - addressed in versions 1.11.0-4.1ubuntu0.24.04.2, 1.11.1-1ubuntu0.25.10.2, 1.11.1-1ubuntu0.26.04.2
libssh2-debuginfo - addressed in versions 1.9.0-12, 1.10.0-10, 1.11.0-7
libssh2-debugsource - addressed in versions 1.9.0-12, 1.10.0-10, 1.11.0-7
libssh2-devel - addressed in versions 1.9.0-12, 1.10.0-10, 1.11.0-7
libssh2-help - addressed in versions 1.9.0-12, 1.10.0-10, 1.11.0-7
libssh2 - addressed in versions 1.9.0-12, 1.10.0-10, 1.11.0-7
libssh2 - update to 1.11.1-1
libssh2-devel - update to 1.11.1-1
libssh2-docs - update to 1.11.1-1
net-libs/libssh2 - update to 1.11.1-r2
libssh2 (Debian package) - update to 1.11.1-1+deb13u1

External References

Related Security Bulletins