Upstream information

CVE-2026-64655 at MITRE

Description

GitHub CLI (gh) is GitHub's official command line tool. Prior to 2.97.0, gh attestation verify builds the certificate Subject Alternative Name matcher from the --signer-repo and --signer-workflow flag values without escaping regex metacharacters, so a user-supplied repository or workflow name is treated as a regular expression rather than a literal string. Because GitHub permits characters such as `.` in organization, repository, and workflow path names and `.` is a regex wildcard, an attacker can register a lookalike name (for example github/artifact.attestations-workflows) that satisfies a matcher intended for a different trusted signer (github/artifact-attestations-workflows), bypassing the intended Sigstore attestation verification. Exploitation requires the attacker to create a plausible lookalike repository and produce valid attestations from it, which could undermine supply chain verification for CI/CD pipelines or policy gates that pin trust to a specific signing workflow. This issue is fixed in version 2.97.0.

SUSE information

Overall state of this security issue: Resolved

This issue is currently rated as having moderate severity.

CVSS v4 Scores
CVSS detail CNA (GitHub)
Base Score 2.1
Vector CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:A/VC:N/VI:N/VA:N/SC:N/SI:L/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
Attack Vector Network
Attack Complexity Low
Attack Requirements Present
Privileges Required None
User Interaction Active
Vulnerable System Confidentiality Impact None
Vulnerable System Integrity Impact None
Vulnerable System Availability Impact None
Subsequent System Confidentiality Impact None
Subsequent System Integrity Impact Low
Subsequent System Availability Impact None
CVSSv4 Version 4.0
SUSE Bugzilla entry: 1276661 [NEW]

No SUSE Security Announcements cross referenced.

List of released packages

Product(s) Fixed package version(s) References
openSUSE Tumbleweed
  • gh >= 2.97.0-1.1
  • gh-bash-completion >= 2.97.0-1.1
  • gh-fish-completion >= 2.97.0-1.1
  • gh-zsh-completion >= 2.97.0-1.1
 Patchnames:
openSUSE-Tumbleweed-2026-11530

SUSE Timeline for this CVE

CVE page created: Tue Aug 18 11:49:31 2026
CVE page last modified: Wed Aug 26 11:46:46 2026