GHSA-8XVP-7HJ6-MCJ9
Vulnerability from github – Published: 2026-05-29 15:30 – Updated: 2026-05-29 15:30Summary
GitHub CLI incorrectly includes an authorization header in API requests to TUF repository mirrors via gh attestation, gh release verify, and gh release verify-asset commands.
Affected users:
- Authenticated
github.comusers who previously rangh attestationcommands,gh release verify, orgh release verify-asset: thegithub.comtoken was included in requests totuf-repo.github.com, a GitHub Pages domain that is not a GitHub API endpoint. All authentication types are affected. - Users with
GH_ENTERPRISE_TOKENorGITHUB_ENTERPRISE_TOKENset who previously rangh attestationcommands,gh release verify, orgh release verify-asset: the enterprise token was included in requests to external hoststuf-repo-cdn.sigstore.devandtmaproduction.blob.core.windows.net. These hosts are not operated by GitHub.
Details
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.
Impact
Tokens were transmitted in HTTP headers to the listed hosts during normal gh attestation, gh release verify, and gh release verify-asset operations. There is no evidence that tokens were logged, retained, or accessed by unauthorized parties. If a token were captured, it would grant the same access as the token holder, potentially including private repositories, organization resources, or enterprise administration depending on token type and permissions.
Remediation and mitigation
- Revoke authentication tokens used with the GitHub CLI:
- Upgrade
ghto2.93.0. - Review personal security logs and any relevant audit logs for actions associated with personal or enterprise accounts.
{
"affected": [
{
"database_specific": {
"last_known_affected_version_range": "\u003c= 2.92.0"
},
"package": {
"ecosystem": "Go",
"name": "github.com/cli/cli/v2"
},
"ranges": [
{
"events": [
{
"introduced": "0"
},
{
"fixed": "2.93.0"
}
],
"type": "ECOSYSTEM"
}
]
}
],
"aliases": [
"CVE-2026-48501"
],
"database_specific": {
"cwe_ids": [
"CWE-863"
],
"github_reviewed": true,
"github_reviewed_at": "2026-05-29T15:30:13Z",
"nvd_published_at": null,
"severity": "HIGH"
},
"details": "### Summary\n\nGitHub CLI incorrectly includes an authorization header in API requests to TUF repository mirrors via `gh attestation`, `gh release verify`, and `gh release verify-asset` commands.\n\n **Affected users:**\n\n - Authenticated `github.com` users who previously ran `gh attestation` commands, `gh release verify`, or `gh release verify-asset`: the `github.com` token was included in requests to `tuf-repo.github.com`, a GitHub Pages domain that is not a GitHub API endpoint. All authentication types are affected.\n - Users with `GH_ENTERPRISE_TOKEN` or `GITHUB_ENTERPRISE_TOKEN` set who previously ran `gh attestation` commands, `gh release verify`, or `gh release verify-asset`: the enterprise token was included in requests to external hosts `tuf-repo-cdn.sigstore.dev` and `tmaproduction.blob.core.windows.net`. These hosts are not operated by GitHub.\n\n### Details\n\nThe 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.\n\nSpecifically, 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\u0027s github.com token. For hosts that don\u0027t match `github.com` or a known GHES instance at all, the resolver falls back to `GH_ENTERPRISE_TOKEN` if set.\n\nThe `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.\n\n### Impact\n\nTokens were transmitted in HTTP headers to the listed hosts during normal `gh attestation`, `gh release verify`, and `gh release verify-asset` operations. There is no evidence that tokens were logged, retained, or accessed by unauthorized parties. If a token were captured, it would grant the same access as the token holder, potentially including private repositories, organization resources, or enterprise administration depending on token type and permissions.\n\n### Remediation and mitigation\n\n1. Revoke authentication tokens used with the GitHub CLI: \n - [Personal access tokens](https://docs.github.com/en/enterprise-cloud@latest/authentication/keeping-your-account-and-data-secure/managing-your-personal-access-tokens)\n - [GitHub CLI OAuth app](https://docs.github.com/en/apps/using-github-apps/reviewing-and-revoking-authorization-of-github-apps#reviewing-your-authorized-github-apps)\n2. Upgrade `gh` to `2.93.0`.\n3. Review personal [security logs](https://docs.github.com/en/authentication/keeping-your-account-and-data-secure/reviewing-your-security-log) and any relevant [audit logs](https://docs.github.com/en/enterprise-cloud@latest/admin/monitoring-activity-in-your-enterprise/reviewing-audit-logs-for-your-enterprise/identifying-audit-log-events-performed-by-an-access-token) for actions associated with personal or enterprise accounts.",
"id": "GHSA-8xvp-7hj6-mcj9",
"modified": "2026-05-29T15:30:13Z",
"published": "2026-05-29T15:30:13Z",
"references": [
{
"type": "WEB",
"url": "https://github.com/cli/cli/security/advisories/GHSA-8xvp-7hj6-mcj9"
},
{
"type": "PACKAGE",
"url": "https://github.com/cli/cli"
},
{
"type": "WEB",
"url": "https://github.com/cli/cli/releases/tag/v2.93.0"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N",
"type": "CVSS_V3"
}
],
"summary": "GitHub CLI has an incorrect authorization header in API requests to TUF repository mirrors via `gh attestation`, `gh release verify`, and `gh release verify-asset` commands"
}
Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or observed by the user.
- Confirmed: The vulnerability has been validated from an analyst's perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.