CVE-2026-3731 libssh SFTP Extension Name sftp.c sftp_extensions_get_data out-of-bounds
Remote attackers can trigger an out-of-bounds read in libssh's SFTP extension handler, potentially causing information disclosure or crashes.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-3731?
CVE-2026-3731 is a medium-severity memory corruption vulnerability in libssh, published on 8 Mar 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
A weakness has been identified in libssh up to 0.11.3. The impacted element is the function sftp_extensions_get_name/sftp_extensions_get_data of the file src/sftp.c of the component SFTP Extension Name Handler. Executing a manipulation of the argument idx can lead to out-of-bounds read. The attack may be performed from remote. Upgrading to version 0.11.4 and 0.12.0 is sufficient to resolve this issue. This patch is called 855a0853ad3abd4a6cd85ce06fce6d8d4c7a0b60. You should upgrade the affected component.
Which versions are affected by CVE-2026-3731?
It affects 1 product.
Linux distribution packages (4)
libssh SUSE:Linux Enterprise Micro 5.2 | All versions | 0.9.8-150200.13.18.1 |
libssh SUSE:Linux Enterprise Module for Basesystem 15 SP7 | All versions | 0.9.8-150600.11.12.1 |
libssh SUSE:Linux Micro 6.1 | All versions | 0.10.6-slfo.1.1_5.1 |
libssh openSUSE:Leap 15.6 | All versions | 0.9.8-150600.11.12.1 |
Products include Libssh Libssh.
How do I fix CVE-2026-3731?
Upgrade to a fixed version.
Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.
Is CVE-2026-3731 being exploited?
There is no known exploitation of CVE-2026-3731 in the wild and no public exploit code.
Other vulnerabilities in libssh
- CVE-2026-59851 Libssh: libssh: authentication bypass via missing gssapi principal check
- CVE-2025-5987 Libssh: invalid return code for chacha20 poly1305 with openssl backend
- CVE-2025-14821 Libssh: libssh: insecure default configuration leads to local man-in-the-middle attacks on windows
- CVE-2012-4560 Memory corruption in n/a
- CVE-2012-4562 Integer overflow in n/a
Sources
Also known as AZL-79544, AZL-79547, BELL-CVE-2026-3731, CLSA-2026-1773830791, CLSA-2026-1773929316, CLSA-2026-1773930007 and 21 more.