CVE-2026-48501 — v2
HIGHCVE-2026-48501 is a high-severity (CVSS 7.4) CWE-863 vulnerability in github.com/cli/cli/v2. A fix is available for github.com/cli/cli/v2 — see the affected versions and patch details below.
GitHub CLI tokens leak via `gh attestation` commands
Exploitation Status
No confirmed exploitation observed yet
- A successful exploit gives an attacker total control of the affected component, not partial access.
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for CVE-2026-48501.
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
How urgent is this, really
CVE-2026-48501 plotted by exploitation likelihood (EPSS) against impact (CVSS). The shaded corner — EPSS 50%+ and CVSS 7.0+ — is where this CVE doesn't sit, though severity or exploitability alone can still warrant action.
Where this sits among everything scored
Of 378,156 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Real counts from FIRST.org, not a sample — log-scaled since the landscape is heavily right-skewed.
Real-World Exposure
github.com/cli/cli/v2Real-time download stats are indexed for npm and PyPI packages. This vulnerability affects Go packages — download data is not available via public APIs for these ecosystems.
Description
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.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 Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐹Go | github.com/cli/cli/v2 | all versions | 2.93.0go get github.com/cli/cli/v2@v2.93.0 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for github.com/cli/cli/v2, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update github.com/cli/cli/v2 to 2.93.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-48501 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like CVE-2026-48501 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2026-48501. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2026-48501 in your dependencies?
O3 Security finds CVE-2026-48501 across Go dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.