GHSA-8gw7-4j42-w388 · Severity: medium · Ecosystem: go — Cosign bundle can be crafted to successfully verify a blob even if the embedded rekorBundle does not reference the given signature
Cosign is a project under the sigstore organization which aims to make signatures invisible infrastructure. In versions prior to 1.12.0 a number of vulnerabilities have been found in cosign verify-blob, where Cosign would successfully verify an artifact when verification should have failed. First a cosign bundle can be crafted to successfully verify a blob even if the embedded rekorBundle does not reference the given signature. Second, when providing identity flags, the email and issuer of a certificate is not checked when verifying a Rekor bundle, and the GitHub Actions identity is never checked. Third, providing an invalid Rekor bundle without the experimental flag results in a successful verification. And fourth an invalid transparency log entry will result in immediate success for verification. Details and examples of these issues can be seen in the GHSA-8gw7-4j42-w388 advisory linked. Users are advised to upgrade to 1.12.0. There are no known workarounds for these issues.
Conclusion & alert: CVE-2022-36056 is rated Exploit Available (50/100): CVSS Medium severity, with low exploitation likelihood (EPSS 0.02%). Core evidence: 1 public exploit reference(s) are indexed (Exploit-DB). Mandatory action: Public exploits are available—assess exposure, apply mitigations, and prioritize patching.
Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.
| EDB-ID | Source | Kind | Published | Link |
|---|---|---|---|---|
| — | nvd_ref | exploit_tag | Exploit-DB ↗ |
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 | 2026-05-28 | 0.07% | 0.02% | -0.05% |
| 2 | 2026-01-18 | 0.04% | 0.07% | +0.03% |
| 3 | 2023-03-07 | — | 0.04% | — |
Full EPSS history (4 records total)
CVSS metrics for this CVE.
| Base score | Version | Severity | Vector | Exploitability | Impact | Score source |
|---|---|---|---|---|---|---|
| 5.5 | 3.1 | MEDIUM |
|
1.8 | 3.6 | [email protected] |
| 5.5 | 3.1 | MEDIUM |
|
1.8 | 3.6 | [email protected] |
GHSA-8gw7-4j42-w388 · Severity: medium · Ecosystem: go — Cosign bundle can be crafted to successfully verify a blob even if the embedded rekorBundle does not reference the given signature
| vendor | priority | summary | link |
|---|---|---|---|
alpine
|
medium | CVE-2022-36056: 1 source package rows (cosign); 11 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 4. | https://security.alpinelinux.org/vuln/CVE-2022-36056 |
debian
|
unimportant | CVE-2022-36056 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-2022-36056 |
redhat
|
low | — | https://access.redhat.com/security/cve/CVE-2022-36056 |
| URL | Tags |
|---|---|
| https://github.com/sigstore/cosign/commit/80b79ed8b4d28ccbce3d279fd273606b5cddcc25 | Patch Third Party Advisory |
| https://github.com/sigstore/cosign/security/advisories/GHSA-8gw7-4j42-w388 | Exploit Mitigation Patch Third Party Advisory |