GHSA-ccxc-vr6p-4858 · Severity: low · Ecosystem: go — Improper Certificate Validation in Cosign
Cosign provides container signing, verification, and storage in an OCI registry for the sigstore project. Prior to version 1.5.2, Cosign can be manipulated to claim that an entry for a signature exists in the Rekor transparency log even if it doesn't. This requires the attacker to have pull and push permissions for the signature in OCI. This can happen with both standard signing with a keypair and "keyless signing" with Fulcio. If an attacker has access to the signature in OCI, they can manipulate cosign into believing the entry was stored in Rekor even though it wasn't. The vulnerability has been patched in v1.5.2 of Cosign. The `signature` in the `signedEntryTimestamp` provided by Rekor is now compared to the `signature` that is being verified. If these don't match, then an error is returned. If a valid bundle is copied to a different signature, verification should fail. Cosign output now only informs the user that certificates were verified if a certificate was in fact verified. There is currently no known workaround.
Conclusion & alert: CVE-2022-23649 is rated Low Risk (15.6/100): CVSS Low severity, with low exploitation likelihood (EPSS 0.02%). Mandatory action: Low composite risk—no urgent action required; patch on your normal maintenance cycle and revisit priority if CVSS or EPSS increases.
Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.
EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).
| # | Date | Old EPSS score | New EPSS score | Delta (New - Old) |
|---|---|---|---|---|
| 1 | 2026-05-26 | 0.05% | 0.02% | -0.03% |
| 2 | 2025-11-21 | 0.02% | 0.05% | +0.03% |
| 3 | 2025-11-18 | — | 0.02% | — |
Full EPSS history (6 records total)
CVSS metrics for this CVE.
| Base score | Version | Severity | Vector | Exploitability | Impact | Score source |
|---|---|---|---|---|---|---|
| 3.3 | 3.1 | LOW |
|
1.8 | 1.4 | [email protected] |
| 3.3 | 3.1 | LOW |
|
1.8 | 1.4 | [email protected] |
| 2.1 | 2.0 | LOW |
|
3.9 | 2.9 | [email protected] |
GHSA-ccxc-vr6p-4858 · Severity: low · Ecosystem: go — Improper Certificate Validation in Cosign
| vendor | priority | summary | link |
|---|---|---|---|
alpine
|
low | CVE-2022-23649: 1 source package rows (cosign); 7 state rows across 7 repos (3.17-community, 3.18-community, 3.19-community, 3.20-community, 3.21-community, 3.22-community, edge-community); fixed 7, open 0. | https://security.alpinelinux.org/vuln/CVE-2022-23649 |
debian
|
unimportant | CVE-2022-23649 unimportant priority: Debian including 1 source packages (cosign), 3 status rows across 3 suites (forky, sid, trixie): resolved 3. | https://security-tracker.debian.org/tracker/CVE-2022-23649 |
suse
|
medium | CVE-2022-23649 severity moderate: SUSE including 9 source package names (cosign, cosign-1.12.0-150400.3.6.1, …), 9 product×package rows across 6 product lines (SUSE Linux Enterprise Module for Basesystem 15 SP4, SUSE Linux Enterprise Module for Basesystem 15 SP5, … (6 product lines)): Fixed 8, Known Not Affected 1. | https://www.suse.com/security/cve/CVE-2022-23649/ |
| URL | Tags |
|---|---|
| https://github.com/sigstore/cosign/commit/96d410a6580e4e81d24d112a0855c70ca3fb5b49 | Patch Third Party Advisory |
| https://github.com/sigstore/cosign/security/advisories/GHSA-ccxc-vr6p-4858 | Third Party Advisory |