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.
CVE-2026-54787
This low-severity CVE scores 3.1 under a secondary CVSS source (NVD's own analysis pending). EPSS exploit probability: 0.1%, top 99% of all CVEs by exploit prediction. GitHub Security Advisory data not yet ingested — confidence will rise once GHSA publishes (typical lag: hours to days for open-source ecosystem CVEs; never for infrastructure-only CVEs).
- Lower severity and no public exploit yet
A fix is available — apply it.
- CVSS v3
- 3.1
- EG Score
- 3.1(medium)
- EG Risk
- 18(Track)EG Risk 18/100SSVC: Track
EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).
How it’s computedSeverity31% × 45%Exploitation0% × 40%Automatability30% × 15%Action: Routine — remediate on your standard cadence. - EPSS PROB
- 0%
- EPSS %ILE
- 1%
- KEV
- Not listed
Published
July 31, 2026
Last Modified
August 1, 2026
References (5)
- security-advisories@githubhttps://github.com/sigstore/sigstore-go/commit/4594ab4c779d08be1f4419803a8249188f35ed5f
- security-advisories@githubhttps://github.com/sigstore/sigstore-go/pull/642
- security-advisories@githubhttps://github.com/sigstore/sigstore-go/releases/tag/v1.2.1
- security-advisories@githubhttps://github.com/sigstore/sigstore-go/security/advisories/GHSA-wqqc-jjcq-vfxm
- 134c704f-9b21-4f2e-91b3-4a467353bcc0https://github.com/sigstore/sigstore-go/security/advisories/GHSA-wqqc-jjcq-vfxm
Vendor Advisories for CVE-2026-54787(4)
These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.
- GHSA-wqqc-jjcq-vfxmGitHub Security AdvisoriesLow
sigstore-go fails to check signature timestamps against a signing key's validity period
- RHSA-2026:47891Red Hat Product SecurityMedium
Red Hat Security Advisory: Red Hat Hardened Images RPMs Security Update
- RHSA-2026:47889Red Hat Product SecurityMedium
Red Hat Security Advisory: Red Hat Hardened Images RPMs Security Update
- RHSA-2026:44162Red Hat Product SecurityHigh
Red Hat Security Advisory: Red Hat Hardened Images RPMs Security Update
Patch Availability(4)
| Vendor / Ecosystem | Fixed in / Patch | Released | Source |
|---|---|---|---|
| redhat | spire1-14-main-1.14.7-0.3.hum1 | 2026-07-29 | redhat |
| redhat | trivy-main-0.72.0-0.1.3.hum1 | 2026-07-29 | redhat |
| redhat | spire1-15-main-1.15.2-0.3.hum1 | 2026-07-23 | redhat |
| redhat | cosign-main-3.1.2-0.2.hum1 | 2026-07-23 | redhat |
Patches are aggregated from vendor advisories (Red Hat, Microsoft, Cisco, GitHub) and package ecosystems (OSV, GHSA). Multiple rows for the same upstream release have been deduplicated.
Affected Packages
(3 across 3 ecosystems)
Debian:13(1)
| Package | Vulnerable range | Fixed in | Dependents |
|---|---|---|---|
| sigstore-go | 0.7.1-2 ... 1.2.2-1 (7 versions) | — | — |
Debian:14(1)
| Package | Vulnerable range | Fixed in | Dependents |
|---|---|---|---|
| sigstore-go | 0.7.1-2, 0.7.3-1, 0.7.3-2, 1.0.0-1, 1.1.4-1 | 1.2.1-1 | — |
Go(1)
| Package | Vulnerable range | Fixed in | Dependents |
|---|---|---|---|
| github.com/sigstore/sigstore-go | — | 1.2.1 | — |
Weakness Classification(1)
MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.
Additional Vendor Advisories
(1)
Vendors that published advisories for this CVE beyond the curated set above. Broader coverage but minimal per-row detail — click through for the original advisory.
Data Freshness Timeline
(refreshed 11× in last 7d / 27× in last 30d)
Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.
- 2026-08-20 22:55 UTCEPSS rescore
- 2026-08-20 05:14 UTCEG score recompute
- 2026-08-20 05:14 UTCVendor advisory
- 2026-08-19 17:04 UTCEPSS rescore
- 2026-08-18 13:48 UTCEPSS rescore
- 2026-08-17 13:47 UTCEPSS rescore
- 2026-08-17 00:25 UTCEG score recompute
- 2026-08-17 00:25 UTCVendor advisory
- 2026-08-16 14:56 UTCEPSS rescore
- 2026-08-16 02:14 UTCEPSS rescore
- 2026-08-15 01:30 UTCEPSS rescore
- 2026-08-13 19:38 UTCVendor advisory
- 2026-08-10 14:52 UTCEG score recompute
- 2026-08-10 14:52 UTCVendor advisory
- 2026-08-09 13:46 UTCEPSS rescore
- 2026-08-08 16:37 UTCEPSS rescore
- 2026-08-07 10:05 UTCEG score recompute
- 2026-08-07 10:05 UTCVendor advisory
- 2026-08-06 13:47 UTCEPSS rescore
- 2026-08-05 19:17 UTCEPSS rescore
- 2026-08-04 15:10 UTCEPSS rescore
- 2026-08-04 05:19 UTCEG score recompute
- 2026-08-04 05:19 UTCVendor advisory
- 2026-08-03 10:36 UTCEPSS rescore
- 2026-08-02 02:27 UTCEPSS rescore
Show 2 moreShow fewer
- 2026-07-31 23:32 UTCEG score recompute
- 2026-07-31 22:07 UTCEG score recompute
Frequently asked(5)
What is CVE-2026-54787?
When was CVE-2026-54787 disclosed?
Is CVE-2026-54787 actively exploited?
What is the CVSS score of CVE-2026-54787?
How do I remediate CVE-2026-54787?
Dependency Blast Radius
See which npm, PyPI, Go, and Maven packages are affected by CVE-2026-54787
Is Your Infrastructure Affected by CVE-2026-54787?
EchelonGraph automatically scans your cloud infrastructure and maps CVE exposure using blast radius analysis.