CriticalCritical vulnerability

CVE-2026-96276 (CVSS 9.8)

NVD · officialPublished Sep 23, 2026Risk 50/100EPSS 0.5%

If a malicious SDK container declares an extension point with a crafted `directory` path, and a developer runs `flatpak build-init --writable-sdk --sdk-extension` with that SDK, attacker-chosen files could be written outside the working directory, since the target path is resolved via a function that allows `..` traversal.

Technical details

CVSS

9.8

AV:NetworkAC:LowPR:NoneUI:NoneC:HighI:HighA:High

Evidence and sources

This record is attributed to NVD. Exploitation status and remediation guidance are kept separate from the vulnerability's technical severity.

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