CVE-2026-96276

Severity CVSS v4.0:

Pending analysis

Type:

CWE-22 Path Traversal

Publication date:

23/09/2026

Last modified:

23/09/2026

Description

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.

Impact

Vector 3.x

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H CVSS v3.1 Severity and Metrics:

Base Score: 9.80 CRITICAL
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Attack Vector (AV): Network
Attack Complexity (AC): Low
Privileges Required (PR): None
User Interaction (UI): None
Scope (S): Unchanged
Confidentiality (C): High
Integrity (I): High
Availability (A): High

Base Score 3.x

9.80

Severity 3.x

CRITICAL

References to Advisories, Solutions, and Tools

https://access.redhat.com/security/cve/CVE-2026-96276
https://bugzilla.redhat.com/show_bug.cgi?id=2539418
https://github.com/flatpak/flatpak/security/advisories/GHSA-8qxj-x646-phcm