CVE-2026-5917
Publication date 11 August 2026
Last updated 24 September 2026
Ubuntu priority
Description
libgit2 versions before 1.8.7 and 1.9.0 before 1.9.7 built with the libssh2 SSH backend (USE_SSH=libssh2) contain a shell command injection vulnerability that allows remote attackers to execute arbitrary commands on an SSH server by supplying a repository path containing unescaped shell metacharacters such as single quotes, semicolons, or pipes. The gen_proto() function in ssh_libssh2.c inserts the repository path directly into a shell command string without escaping special characters before passing it to libssh2_channel_exec(), enabling an attacker to craft a malicious submodule URL in a .gitmodules file that, when processed during a recursive clone, causes the remote server's shell to interpret injected commands under the victim's SSH user account.
Status
| Package | Ubuntu Release | Status |
|---|---|---|
| libgit2 | 26.04 LTS resolute |
Fixed 1.9.1+ds-1ubuntu1.2
|
| 24.04 LTS noble |
Fixed 1.7.2+ds-1ubuntu3.2
|
|
| 22.04 LTS jammy |
Fixed 1.1.0+dfsg.1-4.1ubuntu0.1+esm2
|
|
| 20.04 LTS focal |
Fixed 0.28.4+dfsg.1-2ubuntu0.1+esm2
|
|
| 18.04 LTS bionic |
Fixed 0.26.0+dfsg.1-1.1ubuntu0.2+esm3
|
|
| 16.04 LTS xenial |
Fixed 0.24.1-2ubuntu0.2+esm4
|
|
| 14.04 LTS trusty |
Not affected
|
Get expanded security coverage with Ubuntu Pro
Reduce your average CVE exposure time from 98 days to 1 day with expanded CVE patching, ten-years security maintenance and optional support for the full stack of open-source applications. Free for personal use.
Get Ubuntu Pro 30-day free trialNotes
Severity score breakdown
CVSS version:
Base score
8.6 · High
Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
Base score
8.8 · High
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
References
Related Ubuntu Security Notices (USN)
- USN-8809-1
- libgit2 vulnerability
- 23 September 2026