---
id: CVE-2026-54787
title: sigstore-go is a Go library for Sigstore signing and verification
summary: >-
  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…
severity: low
cvss: 3.1
cvssVector: 'CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:L/A:N'
cwe:
  - CWE-324
vendor: sigstore
product: github.com/sigstore/sigstore-go
affected:
  - github.com/sigstore/sigstore-go <= 1.2.0
patched:
  - github.com/sigstore/sigstore-go 1.2.1
published: '2026-07-31'
updated: '2026-09-10'
sourceUpdated: '2026-09-10T20:30:11.423'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-54787'
references:
  - url: >-
      https://github.com/sigstore/sigstore-go/commit/4594ab4c779d08be1f4419803a8249188f35ed5f
    label: security-advisories@github.com
  - url: 'https://github.com/sigstore/sigstore-go/pull/642'
    label: security-advisories@github.com
  - url: 'https://github.com/sigstore/sigstore-go/releases/tag/v1.2.1'
    label: security-advisories@github.com
  - url: >-
      https://github.com/sigstore/sigstore-go/security/advisories/GHSA-wqqc-jjcq-vfxm
    label: security-advisories@github.com
  - url: >-
      https://github.com/sigstore/sigstore-go/security/advisories/GHSA-wqqc-jjcq-vfxm
    label: 134c704f-9b21-4f2e-91b3-4a467353bcc0
  - url: 'https://github.com/advisories/GHSA-wqqc-jjcq-vfxm'
tags:
  - nvd
  - ghsa
  - go
epss: 0.00134
epssPercentile: 0.02334
aliases:
  - GHSA-wqqc-jjcq-vfxm
ecosystem: go
ingestedAt: '2026-07-31T22:04:41.468Z'
---

## Overview

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.

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.

## Package advisory (CVE-2026-54787)

Affected packages:

- `github.com/sigstore/sigstore-go <= 1.2.0`

Patched in:

- `github.com/sigstore/sigstore-go 1.2.1`

Source: https://github.com/advisories/GHSA-wqqc-jjcq-vfxm