Sigstore Java has a vulnerability with bundle verification of integratedTime
Key facts
- Attack vector
- Local
- Privileges required
- High
- User interaction
- Required
- Attack complexity
- Low
- Impact type
- Security bypass
- Confidentiality · integrity · availability
- None · Low · None
- Fix status
- Fixed
Attack profile from CVSS 3.1 · CNA. Fix status from CNA and GitHub. Impact type from CWE-347.
Summary
sigstore-java is a sigstore java client for interacting with sigstore infrastructure. Version 2.0.0 erroneously removed verification of the integrated (Rekor entry) time) against the Fulcio certificate. Version 2.1.0 re-added this verification with enhancements that adhere to the Sigstore verification spec. The old sigstore-conformance test for this check was built incorrectly. This vulnerability impacts only users verifying bundles with `dev.sigstore:sigstore-java:2.0.0`. Older versions are not affected; it is fixed in `dev.sigstore:sigstore-java:2.1.0` A malicious actor may exploit this if they were able to access a users system and exfiltrate the temporary private key used during signing and then reuse an old fulcio certificate later without requiring direct access to the user's credentials. Users may protect themselves by re-verifying their artifacts using the newest sigstore-java or another current sigstore client. Transparency logs may also be audited for unauthorized signatures for a suspected reused identity.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- Poc
- Automatable
- No
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| sigstore | sigstore-java | = 2.0.0 | — | No fix listed | CNA |
| — | dev.sigstore:sigstore-java (Maven) | 2.0.0 to before 2.1.0 | 2.1.0 | Patch available | GHSA-qqw8-7c2r-jxch |
- sigstore-java Vendorsigstore Affected = 2.0.0 Fixed in — No fix listed CNA
- dev.sigstore:sigstore-java (Maven) Vendor— Affected 2.0.0 to before 2.1.0 Fixed in 2.1.0 Patch available GHSA-qqw8-7c2r-jxch
Remediation
- Fix · GHSA-qqw8-7c2r-jxch dev.sigstore:sigstore-java (Maven) Fixed in 2.1.0 Advisory →
Timeline
- 2026-10-02 Threatist record created from CVE-2026-48791
- 2026-10-03 Alias added: GHSA-qqw8-7c2r-jxch
References
Other 6
- https://github.com/sigstore/sigstore-java/security/advisories/GHSA-qqw8-7c2r-jxch
- https://github.com/sigstore/sigstore-java/pull/1008
- https://github.com/sigstore/sigstore-java/pull/1185
- https://github.com/sigstore/sigstore-java/commit/4b7a49ebb1813f5b1ff113bcad63246358222d61
- https://github.com/sigstore/sigstore-java/commit/b529335728fc5cfb574161b4b3c06859a8a2aa88
- https://github.com/sigstore/sigstore-java
More sigstore vulnerabilities
- TI-2022-16356 False positive signature verification in cosign CVSS 3.1CRITICAL 9.8
- TI-2026-36084 sigstore-js: `certificateOIDs` verification constraints are silently dropped and never enforced CVSS 3.1HIGH 7.5
- TI-2024-19670 Cosign vulnerable to machine-wide denial of service via malicious artifacts CVSS 3.1HIGH 7.5
- TI-2026-18290 Fulcio vulnerable to Server-Side Request Forgery (SSRF) via MetaIssuer Regex Bypass CVSS 3.1MEDIUM 5.8
- TI-2026-36085 sigstore-js: Insufficient Verification of Data Authenticity CVSS 3.1MEDIUM 6.5
- TI-2024-19669 Cosign vulnerable to system-wide denial of service via malicious attachments CVSS 3.1MEDIUM 5.9
Sources
- CVE-2026-48791 · CVE Program
- CVE-2026-48791 · NVD
- FIRST EPSS
- GHSA-qqw8-7c2r-jxch · GitHub Advisory Database · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences