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CVE-2026-56280 (GCVE-0-2026-56280)

Vulnerability from cvelistv5 – Published: 2026-06-22 21:04 – Updated: 2026-06-24 18:05
VLAI
Title
Cap-go - Privilege Inversion in Build Log Stream via SSE Disconnect
Summary
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.
SSVC
Exploitation: poc Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-06-24 18:04 UTC
CWE
References
Impacted products
Vendor Product Version CPE status
Cap-go capgo Affected: 0 , < 12.128.2 (semver)
Unaffected: 12.128.2 (semver)
guessed Create a notification for this product.
Date Public
2026-05-07 00:00
Credits
Show details on NVD website

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