{"items":[{"id":"NVI-00015412","kind":"vulnerability","title":"Claude Code Action: Malicious MCP Server Configuration in PRs Enables Remote Code Execution and Secret Exfiltration","revision":3,"unknowns":["Customer inventory, deployment, reachability and exploitation have not been inspected."],"lifecycle":"active","identifiers":["GHSA-8q5r-mmjf-575q","CVE-2026-47751"],"plain_summary":"GitHub lists this reviewed advisory for anthropics/claude-code-action. Published version ranges and source prerequisites are shown below; this is not an inspection of a visitor’s application.","review_status":"source_listed","control_topics":[],"public_actions":[{"summary":"Identify the exact component and deployed version, examine the linked publisher’s conditions, and retain evidence of any mitigation.","source_ids":["sr-158b02179d422b45aa5b54866b09c721"],"action_type":"investigate","limitations":"Confirm current vendor support, compatibility and deployment evidence. This report has not tested a fix in your system.","current_supported_target":null}],"schema_version":"1.1.0","source_metrics":[{"kind":"EPSS","as_of":"2026-11-04T12:03:12.000Z","value":"0.766%","meaning":"FIRST EPSS model v2026.06.15; exploitation probability over 30 days, percentile 0.55607. Missing scores are unknown.","source_id":"sr-158b02179d422b45aa5b54866b09c721"}],"why_it_matters":"Published affected context helps an owner decide what evidence to gather. This report has not examined your application.","related_sources":[{"id":"sr-65948ec62926aa0fafbf28188be18dc2","url":"https://github.com/advisories/GHSA-8q5r-mmjf-575q","basis":"vendor_advisory","notes":"GitHub Advisory Database; CC-BY-4.0. Each advisory links its original attribution. Null normalizes fields.","title":"GHSA-8q5r-mmjf-575q","publisher":"GitHub Advisory Database","observed_at":"2026-11-02T02:21:58.521Z"},{"id":"sr-158b02179d422b45aa5b54866b09c721","url":"https://www.first.org/epss/data.html","basis":"official_catalog","notes":"FIRST EPSS; probability of exploitation in the next 30 days, not local compromise. Dataset date/model retained; FIRST services terms apply.","title":"CVE-2026-47751","publisher":"FIRST EPSS","observed_at":"2026-11-04T17:58:50.329Z"}],"affected_context":[{"certainty":"source_listed","source_ids":["sr-65948ec62926aa0fafbf28188be18dc2"],"technology":"anthropics/claude-code-action","known_exclusions":[],"conditions_summary":"Due to the combination of checking out PR head branches (attacker-controlled), reading `.mcp.json` from the working directory via default setting sources, and unconditionally enabling all project MCP servers via `enableAllProjectMcpServers`, it was possible for an attacker who opened a PR containing a malicious `.mcp.json` file to achieve arbitrary code execution on the GitHub Actions runner. This could lead to exfiltration of secrets available to the workflow (such as API keys and tokens) when a privileged user triggered the Claude action on the PR. Exploiting this required the ability to open a pull request against a repository using the claude-code-action and a privileged user or automatic trigger to invoke the action on that PR.\n\nUsers pinned to a vulnerable version of claude-code-action are advised to update to the latest version. Users referencing anthropics/claude-code-action@v1, anthropics/claude-code-action@beta, anthropics/claude-code-action@main, or other non-pinned tags will have received this fix already\n\nClaude Code thanks hackerone.com/reptou for reporting this issue.","public_affected_ranges":["< 1.0.74"]}],"null_published_at":"2026-11-08T19:53:38.929Z","source_updated_at":"2026-09-01T00:59:51.000Z","source_disclosed_at":"2026-06-10T19:33:48.000Z","is_synthetic_fixture":false,"null_last_reviewed_at":null,"public_change_summary":"Dated EPSS estimate updated; this is not a new disclosure or proof of exploitation.","null_first_observed_at":"2026-11-02T02:21:58.521Z"},{"id":"NVI-00015412","kind":"vulnerability","title":"Claude Code Action: Malicious MCP Server Configuration in PRs Enables Remote Code Execution and Secret Exfiltration","revision":1,"unknowns":["Customer inventory, deployment, reachability and exploitation have not been inspected."],"lifecycle":"active","identifiers":["GHSA-8q5r-mmjf-575q","CVE-2026-47751"],"plain_summary":"GitHub lists this reviewed advisory for anthropics/claude-code-action. Published version ranges and source prerequisites are shown below; this is not an inspection of a visitor’s application.","review_status":"source_listed","control_topics":[],"public_actions":[{"summary":"Identify the exact component and deployed version, examine the linked publisher’s conditions, and retain evidence of any mitigation.","source_ids":["sr-65948ec62926aa0fafbf28188be18dc2"],"action_type":"investigate","limitations":"Confirm current vendor support, compatibility and deployment evidence. This report has not tested a fix in your system.","current_supported_target":null}],"schema_version":"1.1.0","source_metrics":[],"why_it_matters":"Published affected context helps an owner decide what evidence to gather. This report has not examined your application.","related_sources":[{"id":"sr-65948ec62926aa0fafbf28188be18dc2","url":"https://github.com/advisories/GHSA-8q5r-mmjf-575q","basis":"vendor_advisory","notes":"GitHub Advisory Database; CC-BY-4.0. Each advisory links its original attribution. Null normalizes fields.","title":"GHSA-8q5r-mmjf-575q","publisher":"GitHub Advisory Database","observed_at":"2026-11-02T02:21:58.521Z"}],"affected_context":[{"certainty":"source_listed","source_ids":["sr-65948ec62926aa0fafbf28188be18dc2"],"technology":"anthropics/claude-code-action","known_exclusions":[],"conditions_summary":"Due to the combination of checking out PR head branches (attacker-controlled), reading `.mcp.json` from the working directory via default setting sources, and unconditionally enabling all project MCP servers via `enableAllProjectMcpServers`, it was possible for an attacker who opened a PR containing a malicious `.mcp.json` file to achieve arbitrary code execution on the GitHub Actions runner. This could lead to exfiltration of secrets available to the workflow (such as API keys and tokens) when a privileged user triggered the Claude action on the PR. Exploiting this required the ability to open a pull request against a repository using the claude-code-action and a privileged user or automatic trigger to invoke the action on that PR.\n\nUsers pinned to a vulnerable version of claude-code-action are advised to update to the latest version. Users referencing anthropics/claude-code-action@v1, anthropics/claude-code-action@beta, anthropics/claude-code-action@main, or other non-pinned tags will have received this fix already\n\nClaude Code thanks hackerone.com/reptou for reporting this issue.","public_affected_ranges":["< 1.0.74"]}],"null_published_at":"2026-11-03T10:03:31.363Z","source_updated_at":"2026-09-01T00:59:51.000Z","source_disclosed_at":"2026-06-10T19:33:48.000Z","is_synthetic_fixture":false,"null_last_reviewed_at":null,"public_change_summary":"First indexed by Null; source disclosure date is shown separately.","null_first_observed_at":"2026-11-02T02:21:58.521Z"}],"next_cursor":null,"snapshot_revision":"42594"}