CVE-2026-54787
sigstore-go fails to check signature timestamps against a signing key's validity period
Description
sigstore-go is a Go library for Sigstore signing and verification. Prior to 1.2.1, sigstore-go does not check a bundle signing timestamp against the validity window of an ExpiringKey wrapping a self-managed long-lived signing key without a certificate, which can allow an attacker holding expired key material to sign accepted bundles. This issue is fixed in version 1.2.1.
INFO
Published Date :
July 31, 2026, 11:17 p.m.
Last Modified :
Aug. 1, 2026, 12:17 a.m.
Remotely Exploit :
Yes !
Source :
[email protected]
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS | 134c704f-9b21-4f2e-91b3-4a467353bcc0 | |||||
| CVSS 3.1 | LOW | [email protected] | ||||
| CVSS 3.1 | LOW | MITRE-CVE |
Solution
- Update sigstore-go to version 1.2.1.
- Ensure signing timestamps are validated.
- Rotate signing keys if compromised.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-54787.
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-54787 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-54787
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-54787 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-54787 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0
Aug. 01, 2026
Action Type Old Value New Value Added Reference https://github.com/sigstore/sigstore-go/security/advisories/GHSA-wqqc-jjcq-vfxm Added SSVC {'id': 'CVE-2026-54787', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'none'}, {'automatable': 'no'}, {'technicalImpact': 'partial'}], 'version': '2.0.3', 'timestamp': '2026-07-31T23:35:40.966529Z'} -
New CVE Received by [email protected]
Jul. 31, 2026
Action Type Old Value New Value Added Affected [{'vendor': 'sigstore', 'product': 'sigstore-go', 'versions': [{'status': 'affected', 'version': '< 1.2.1'}]}] Added Description sigstore-go is a Go library for Sigstore signing and verification. Prior to 1.2.1, sigstore-go does not check a bundle signing timestamp against the validity window of an ExpiringKey wrapping a self-managed long-lived signing key without a certificate, which can allow an attacker holding expired key material to sign accepted bundles. This issue is fixed in version 1.2.1. Added CVSS V3.1 AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:L/A:N Added CWE CWE-324 Added Reference https://github.com/sigstore/sigstore-go/commit/4594ab4c779d08be1f4419803a8249188f35ed5f Added Reference https://github.com/sigstore/sigstore-go/pull/642 Added Reference https://github.com/sigstore/sigstore-go/releases/tag/v1.2.1 Added Reference https://github.com/sigstore/sigstore-go/security/advisories/GHSA-wqqc-jjcq-vfxm