CVE-2026-29058: WWBN AVideo is vulnerable to unauthenticated OS Command Injection via base64Url in objects/getImage.php

Should you act?

Critical and remotely reachable

No known exploitation yet, but it is network-reachable without credentials. This signal is computed from CISA KEV, EPSS and CVSS data; it is not an editorial verdict.

• No confirmed exploitation. It is not in CISA’s KEV catalog and CISA’s SSVC assessment records no known exploitation. That can change quickly after a public write-up; re-check if you are affected.
• EPSS 6.8%, percentile 94: FIRST’s model estimates a 6.8% chance of exploitation activity in the next 30 days, higher than 94% of all scored CVEs (elevated). EPSS is a probability, not a verdict.
• Remotely reachable with no login and no user interaction. If the vulnerable service is exposed to the internet, prioritize it.
• Only applies if your dependency tree includes wwbn/avideo (Composer (PHP)) < 7.0.0, fixed in 7.0.0. Check your lockfile, including transitive dependencies.

What it is

AVideo is a video-sharing Platform software. Prior to version 7.0, an unauthenticated attacker can execute arbitrary OS commands on the server by injecting shell command substitution into the base64Url GET parameter. This can lead to full server compromise, data exfiltration (e.g., configuration secrets, internal keys, credentials), and service disruption. This issue has been patched in version 7.0.

From the GitHub advisory

Impact

An unauthenticated attacker can execute arbitrary OS commands on the server by injecting shell command substitution into the base64Url GET parameter. This can lead to full server compromise, data exfiltration (e.g., configuration secrets, internal keys, credentials), and service disruption.

Root Cause

The base64Url parameter is Base64-decoded and then interpolated directly into a double-quoted ffmpeg shell command without proper shell escaping. The upstream validation uses FILTERVALIDATEURL, which validates URL syntax but does not prevent shell metacharacters / command substitution sequences from being interpreted by the shell.

Affected Components

Weakness type: CWE-78.

Product: wwbn/avideo (Composer (PHP)) · Assigned by: GitHub_M · Published: 2026-03-06

Affected and fixed versions

Severity scores

• Attack vector: network (remotely reachable)
• Attack complexity: low
• Privileges required: none (no login)
• User interaction: none
• Scope: unchanged

CVSS measures how bad a flaw is if exploited, not how likely exploitation is. Read it next to the exploitation data below.

Exploitation and urgency

• CISA KEV: not listed (no confirmed in-the-wild exploitation known to CISA).
• CISA SSVC assessment: exploitation none, automatable yes, technical impact total.
• FIRST EPSS (model of 2026-10-21): 6.77% probability of exploitation activity in the next 30 days; percentile 94.

Timeline

• 2026-03-03 — GitHub-reviewed advisory GHSA-9j26-99jh-v26q published (critical)
• 2026-03-06 — CVE record published by GitHub_M
• 2026-03-09 — CVE record last updated

Sources and references

Original sources first. Version and fix details should always be confirmed against the vendor or project advisory.

Vulnerability records

1. GitHub Advisory GHSA-9j26-99jh-v26q github.com
2. CVE.org record CVE-2026-29058 cve.org
3. NVD entry CVE-2026-29058 nvd.nist.gov

Other references from the CVE record and advisory

1. github.com github.com

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