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GHSA-wqqc-jjcq-vfxm

LOW

GHSA-wqqc-jjcq-vfxm is a low-severity (CVSS 3.1) CWE-324 vulnerability in github.com/sigstore/sigstore-go. O3 Security confirms whether GHSA-wqqc-jjcq-vfxm is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.

sigstore-go fails to check signature timestamps against a signing key's validity period

Also known asCVE-2026-54787
Published
Jul 31, 2026
Updated
Aug 1, 2026
Affected
1 pkg
Patched
1 / 1
Exploits
None indexed

Blast Radius

1 pkg affected
🐹github.com/sigstore/sigstore-go

Real-time download stats are indexed for npm and PyPI packages. This vulnerability affects Go packages — download data is not available via public APIs for these ecosystems.

Description

sigstore-go fails to check signature timestamps against a signing key's validity period for self-managed long-lived keys without certificates.

Impact

To verify a bundle with a self-managed long-lived key, the key needs to be wrapped in an ExpiringKey type that implies expiration semantics:

signatureVerifier, _ := signature.LoadDefaultVerifier(publicKey)
expiredKey := root.NewExpiringKey(signatureVerifier, time.Unix(0, 0), time.Unix(1, 0))

Despite the API contract, the validator does not check the bundle signing time against the validity window. Attackers that obtain expired key materials may be able to sign bundles with those materials that are accepted despite a configured expiry date. This issue only impacts the long-lived signing key workflow, and not standard deployments involving a certificate authority.

Reproduction steps

Start from a sigstore-go checkout:

git clone https://github.com/sigstore/sigstore-go.git
cd sigstore-go
git checkout 8ca80c47ef03d26ebf174db7c296700b075b2c16

Apply the patch containing the test case and associated materials:

git apply sigstore-go-public-key-validity-test.patch

Run the test:

go test ./pkg/verify -run TestPublicKeyValidityCheckedAgainstSignedTimestamp

On vulnerable code, the test fails because verification succeeds even though the trusted ExpiringKey is not valid at the signed timestamp:

--- FAIL: TestPublicKeyValidityCheckedAgainstSignedTimestamp
    signed_entity_test.go:602:
        	Error:      	An error is expected but got nil.

Affected Packages

1 total 1 fixed
EcosystemPackageVulnerable rangeFix
🐹Gogithub.com/sigstore/sigstore-goall versions1.2.1

Detection & mitigation playbook

Open-source dependency
  1. Detect

    Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for github.com/sigstore/sigstore-go. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.

  2. Fix

    Update github.com/sigstore/sigstore-go to 1.2.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-wqqc-jjcq-vfxm is resolved across your whole dependency graph.

  3. Workarounds

    If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.

  4. How O3 protects you

    O3 pinpoints whether GHSA-wqqc-jjcq-vfxm is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.

Tailored to GHSA-wqqc-jjcq-vfxm. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.

Frequently Asked Questions

sigstore-go fails to check signature timestamps against a signing key's validity period for self-managed long-lived keys without certificates. ## Impact To verify a bundle with a self-managed long-lived key, the key needs to be wrapped in an `ExpiringKey` type that implies expiration semantics: ```go signatureVerifier, _ := signature.LoadDefaultVerifier(publicKey) expiredKey := root.NewExpiringKey(signatureVerifier, time.Unix(0, 0), time.Unix(1, 0)) ``` Despite the API contract, the validator does not check the bundle signing time against the validity window. Attackers that obtain expired
O3 Security · Impact-Aware SCA

Is GHSA-wqqc-jjcq-vfxm in your dependencies?

O3 detects GHSA-wqqc-jjcq-vfxm across Go dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.