CVE-2026-56280
Cap-go before 12.128.2 contains a privilege inversion vulnerability in GET /build/logs/:jobId that allows read-only API key holders to cancel running native builds. The endpoint registers an abort listener on the SSE stream that unconditionally invokes cancelBuildOnDisconnect() using the privileged server-side BUILDER_API_KEY when clients disconnect, bypassing the app.build_native permission check required by the explicit POST /build/cancel/:jobId endpoint. Attackers with read-only API keys can repeatedly disrupt native build operations and CI/CD workflows by opening the log stream and dropping the connection.
- Score
- CVSS 4.0 7.1 High
- Status
- Deferred - disclosure@vulncheck.com
- Published
- 2026-06-22
- Last modified
- 2026-10-25
- Weaknesses
- CWE-862
Affected products
References
- https://github.com/Cap-go/capgo/security/advisories/GHSA-95g7-xwwx-j737
- https://www.vulncheck.com/advisories/cap-go-privilege-inversion-in-build-log-stream-via-sse-disconnect
