RCE in Libgit2
CVE-2026-5917
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.
Vulnerability class: Command Injection (OS Command Injection)
Published · last modified .
CVSS v3 metric
CVSS v3 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.
EPSS exploit prediction
EPSS: 0.014 (71.8th percentile), scored .
Low probability of exploitation in the next 30 days, but still tracked. 72nd percentile — 71.8% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.009 · newest: 0.014 · change: +0.005
Affected products
- Libgit2 — versions 0.27.0
Weakness classification (CWE)
References
- github.com/libgit2/libgit2 (product)
- www.vulncheck.com/advisories/libgit2-shell-command-injection-via-ssh-libssh2-ba… (third-party-advisory)
- github.com/libgit2/libgit2/security/advisories/GHSA-xqj4-2j5v-rr75 (vendor-advisory, patch)
Frequently asked questions
- What is CVE-2026-5917?
- CVE-2026-5917 is a high-severity vulnerability in Libgit2, classified under OS Command Injection. CVSS score: 8.8/10. Published 2026-08-11.
- How severe is CVE-2026-5917?
- High severity. CVSS v3 base score is 8.8 out of 10.