CVE-2026-54787

LOW

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

Title source: cna
STIX 2.1

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.

Scores

CVSS v3 3.1
EPSS 0.0009
EPSS Percentile 0.5%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:L/A:N

CISA SSVC

Vulnrichment
Exploitation none
Automatable no
Technical Impact partial

Details

CWE
CWE-324
Status published
Products (2)
sigstore/sigstore-go 0 - 1.2.1Go
sigstore/sigstore-go < 1.2.1
Published Jul 31, 2026
Tracked Since Aug 01, 2026