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CVE-2026-33482

AVideo has an OS Command Injection via $() Shell Substitution Bypass in sanitizeFFmpegCommand()

CVSS 8.1 HIGHEPSS 2.1%CWE-78
In short

AVideo's command sanitization function doesn't block shell command substitution syntax `$()`, allowing attackers to execute arbitrary operating system commands on the video encoder server through crafted encrypted payloads.

Technical detail

The `sanitizeFFmpegCommand()` function in AVideo ≤26.0 strips common shell metacharacters but fails to filter `$()` bash substitution syntax; when the sanitized command is executed via `sh -c` in a double-quoted context, an attacker can inject arbitrary commands through a valid encrypted payload, bypassing the intended command injection protections (CWE-78).

Summary generated and translated by AI from the official description.
WWBN AVideo is an open source video platform. In versions up to and including 26.0, the `sanitizeFFmpegCommand()` function in `plugin/API/standAlone/functions.php` is designed to prevent OS command injection in ffmpeg commands by stripping dangerous shell metacharacters (`&&`, `;`, `|`, `` ` ``, `<`, `>`). However, it fails to strip `$()` (bash command substitution syntax). Since the sanitized command is executed inside a double-quoted `sh -c` context in `execAsync()`, an attacker who can craft a valid encrypted payload can achieve arbitrary command execution on the standalone encoder server. Commit 25c8ab90269e3a01fb4cf205b40a373487f022e1 contains a patch.
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
Affected products
WWBN · AVideo

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