Auth bypass in Cli
CVE-2026-48501
GitHub CLI (gh) is GitHub’s official command line tool. Prior to 2.93.0, GitHub CLI incorrectly includes authorization header in API requests to TUF repository mirrors via gh attestation, gh release verify, and gh release verify-asset commands. The CLI uses a shared HTTP client with an authentication layer that automatically attaches tokens to outgoing requests. This layer lacks accurate host detection and can incorrectly attribute the target host, providing it with a token it should never receive. Specifically, the host normalization logic collapses any *.github.com subdomain to github.com, so a request to tuf-repo.github.com (a GitHub Pages site, not a GitHub API endpoint) is treated as a request to github.com and receives the user's github.com token. For hosts that don't match github.com or a known GHES instance at all, the resolver falls back to GH_ENTERPRISE_TOKEN if set. The gh attestation, gh release verify and gh release verify-asset commands fetch data from several external hosts as part of their normal operation (TUF metadata from tuf-repo.github.com and tuf-repo-cdn.sigstore.dev, artifact bundles from Azure Blob Storage). Because these requests go through the same authenticated HTTP client, the token is sent to all of them. This vulnerability is fixed in 2.93.0.
Vulnerability class: Broken Access Control
EPSS: 0.003 (21.1th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 7.4 (High). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N.
Affected products
- Cli — versions < 2.93.0
- Github Cli
Weakness classification (CWE)
References
- security-advisories@github.com (x_refsource_CONFIRM, Mitigation, Vendor Advisory)
Frequently asked questions
- What is CVE-2026-48501?
- CVE-2026-48501 is a high-severity vulnerability in Cli, classified under Incorrect Authorization. CVSS score: 7.4/10. Published 2026-05-29.
- How severe is CVE-2026-48501?
- High severity. CVSS v3 base score is 7.4 out of 10.