What is CVE-2023-22742?

CVE-2023-22742 is a medium-severity vulnerability in Libgit2, classified under Improper Verification of Cryptographic Signature. CVSS score: 5.3/10. Published 2023-01-20.

How severe is CVE-2023-22742?

Medium severity. CVSS v3 base score is 5.3 out of 10.

Vulnerability in Libgit2

CVE-2023-22742

libgit2 is a cross-platform, linkable library implementation of Git. When using an SSH remote with the optional libssh2 backend, libgit2 does not perform certificate checking by default. Prior versions of libgit2 require the caller to set the `certificate_check` field of libgit2's `git_remote_callbacks` structure - if a certificate check callback is not set, libgit2 does not perform any certificate checking. This means that by default - without configuring a certificate check callback, clients will not perform validation on the server SSH keys and may be subject to a man-in-the-middle attack. Users are encouraged to upgrade to v1.4.5 or v1.5.1. Users unable to upgrade should ensure that all relevant certificates are manually checked.

Published 2023-01-20 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 5.3 (Medium). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:N/I:H/A:N.

EPSS exploit prediction

EPSS: 0.006 (45.5th percentile), scored 2026-09-30.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 46th percentile — 45.5% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.006 · newest: 0.006 · change: 0.000

Affected products

Libgit2 — versions = 1.5.0, < 1.4.5, 1.5.0

Weakness classification (CWE)

CWE-347 — Improper Verification of Cryptographic Signature

References

github.com/libgit2/libgit2/security/advisories/GHSA-8643-3wh5-rmjq (Third Party Advisory)
github.com/libgit2/libgit2/commit/42e5db98b963ae503229c63e44e06e439df50e56 (Patch, Third Party Advisory)
github.com/libgit2/libgit2/commit/cd6f679af401eda1f172402006ef8265f8bd58ea (Patch, Third Party Advisory)
github.com/libgit2/libgit2/releases/tag/v1.4.5 (Third Party Advisory, Release Notes)
github.com/libgit2/libgit2/releases/tag/v1.5.1 (Third Party Advisory, Release Notes)
www.libssh2.org (Third Party Advisory)
www.openwall.com/lists/oss-security/2023/11/06/5

Frequently asked questions

What is CVE-2023-22742?: CVE-2023-22742 is a medium-severity vulnerability in Libgit2, classified under Improper Verification of Cryptographic Signature. CVSS score: 5.3/10. Published 2023-01-20.
How severe is CVE-2023-22742?: Medium severity. CVSS v3 base score is 5.3 out of 10.