What is the CVSS score of CVE-2026-48501?

CVE-2026-48501 has a CVSS 3.1 base score of 7.4 (High). CVSS vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N. EPSS exploitation probability: 0.0%.

Which versions of GitHub CLI are affected by CVE-2026-48501?

GitHub CLI versions through 2.92.0 leak authentication tokens to external hosts during attestation and release verification commands, affecting developers and enterprise users.. A patch is available.

How to fix or mitigate CVE-2026-48501?

Within 24 hours: Audit inventory of GitHub CLI version 2.92.0 or earlier across development environments; identify usage of affected commands (gh attestation, gh release verify, gh release verify-asset). Within 7 days: Rotate all personal access tokens, GitHub App tokens, and enterprise tokens; restrict token scopes to minimum required permissions. Within 30 days: Disable affected commands via organizational policy if not critical; implement enhanced token activity monitoring; apply vendor patch immediately upon release.

GitHub CLI CVE-2026-48501

EUVD-2026-33340 HIGH

Incorrect Authorization (CWE-863)

2026-05-29 https://github.com/cli/cli

GHSA-8xvp-7hj6-mcj9

Microsoft Authentication Bypass Red Hat

7.4

CVSS 3.1 · GitHub Advisory

Severity by source

GitHub Advisory PRIMARY

7.4 HIGH

AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N

SUSE

HIGH

qualitative

Red Hat

6.8 MEDIUM

qualitative

Primary rating from GitHub Advisory.

CVSS VectorGitHub Advisory

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N

Attack Vector

Network

Attack Complexity

High

Privileges Required

None

User Interaction

None

Scope

Unchanged

Confidentiality

High

Integrity

High

Availability

None

Lifecycle Timeline

Patch available

May 29, 2026 - 17:02 EUVD

Source Code Evidence Fetched

May 29, 2026 - 15:50 vuln.today

Analysis Generated

May 29, 2026 - 15:50 vuln.today

CVE Published

May 29, 2026 - 15:30 nvd

HIGH 7.4

DescriptionGitHub Advisory

Summary

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.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.
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.

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 gh to 2.93.0.
Review personal security logs and any relevant audit logs for actions associated with personal or enterprise accounts.

AnalysisAI

Token leakage in GitHub CLI versions through 2.92.0 causes authentication tokens to be transmitted to unintended hosts when users run gh attestation, gh release verify, or gh release verify-asset commands. The flawed host normalization collapses *.github.com subdomains to github.com, leaking github.com tokens to tuf-repo.github.com (a GitHub Pages domain), while GH_ENTERPRISE_TOKEN values leak to external hosts tuf-repo-cdn.sigstore.dev and tmaproduction.blob.core.windows.net. No public exploit identified at time of analysis, and the vendor (GitHub) reports no evidence that tokens were captured or misused.

Technical ContextAI

The vulnerability resides in the GitHub CLI (github.com/cli/cli/v2), a Go-based command-line tool for interacting with GitHub. The CLI uses a shared HTTP client with an authentication middleware layer that automatically attaches bearer tokens to outgoing requests. The host normalization logic incorrectly collapses any *.github.com subdomain to the canonical github.com identifier, and unknown hosts fall through to GH_ENTERPRISE_TOKEN if set. This is a classic CWE-863 (Incorrect Authorization) defect: the authorization decision (whether to attach a credential) is made on a host identity that has been incorrectly resolved, sending sensitive credentials to TUF repository mirrors and Azure Blob Storage endpoints that have no legitimate need for them and are not operated by GitHub.

RemediationAI

Vendor-released patch: 2.93.0 - upgrade gh to version 2.93.0 or later (https://github.com/cli/cli/releases/tag/v2.93.0). Because tokens may have already been transmitted to unintended hosts, GitHub advises revoking and rotating any authentication tokens previously used with the affected CLI, including personal access tokens and the GitHub CLI OAuth app authorization, then reviewing personal security logs and enterprise audit logs for any anomalous actions tied to those tokens. As a workaround prior to upgrading, avoid running gh attestation, gh release verify, and gh release verify-asset; if those commands are required, unset GH_ENTERPRISE_TOKEN and GITHUB_ENTERPRISE_TOKEN before invocation to prevent enterprise tokens from leaking to sigstore and Azure Blob Storage hosts, accepting that github.com token leakage to tuf-repo.github.com cannot be avoided without the patch and that disabling these commands also disables artifact attestation verification. Full advisory: https://github.com/cli/cli/security/advisories/GHSA-8xvp-7hj6-mcj9.