Vulnerability · Published May 29, 2026 · Assigned by GitHub_M
CVE-2026-48501GitHub CLI tokens leak via `gh attestation` commands
High 7.4
In plain English
A high-severity incorrect authorization in cli from cli. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.3% (higher than 22% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official description
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.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian:12 | gh | no fix listed | DEBIAN-CVE-2026-48501 |
| Debian:13 | gh | no fix listed | DEBIAN-CVE-2026-48501 |
| Go | github.com/cli/cli | no fix listed | GO-2026-5271 |
| Go | github.com/cli/cli/v2 | 2.93.0 | GHSA-8xvp-7hj6-mcj9 |
| Go | github.com/cli/cli/v2 | 2.93.0 | GO-2026-5271 |
| Ubuntu:24.04:LTS | golang-github-cli-go-gh | no fix listed | UBUNTU-CVE-2026-48501 |
| Ubuntu:25.10 | golang-github-cli-go-gh | no fix listed | UBUNTU-CVE-2026-48501 |
| Ubuntu:26.04:LTS | golang-github-cli-go-gh | no fix listed | UBUNTU-CVE-2026-48501 |
| Ubuntu:25.10 | golang-github-cli-go-gh-v2 | no fix listed | UBUNTU-CVE-2026-48501 |
| Ubuntu:26.04:LTS | golang-github-cli-go-gh-v2 | no fix listed | UBUNTU-CVE-2026-48501 |
Affected products (as reported)
Weakness: CWE-863 · Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N
References
- https://github.com/cli/cli/security/advisories/GHSA-8xvp-7hj6-mcj9 x_refsource_CONFIRM