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.

CVSS v3 7.1 HIGH

7.1^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.8 / Impact : 4.2

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact LOW

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
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
https://github.com/Cap-go/capgo/security/advisories/GHSA-95g7-xwwx-j737

Configurations

No configuration.

History

No history.

Information

Published : 2026-06-22 22:16

Updated : 2026-06-24 19:17

NVD link : CVE-2026-56280

Mitre link : CVE-2026-56280

CVE.ORG link : CVE-2026-56280

JSON object : View

Products Affected

No product.

CWE

CWE-862

Missing Authorization

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