Critical · CVSS 9.3CVE-2026-77138

Remote Code Execution in extension "HTML5 Video Player vs. Powermail" (html5videoplayer_powermail)CVE-2026-77138

Answer in brief

CVE-2026-77138 records a Critical severity (CVSS 9.3) vulnerability in Remote Code Execution in extension "HTML5 Video Player vs. Powermail" (html5videoplayer_powermail). The current sources do not mark it as known exploited. The current feed maps TYPO3/Extension "HTML5 Video Player vs. Powermail" (generic), TYPO3/lochmueller/html5videoplayer-powermail (generic). Check affected ranges and fixed versions before updating.

Analysis pending evidence review

HOL Guard separates source facts from reviewed analysis. See the methodology.

Published Aug 25, 2026Updated Sep 28, 2026Source checked Oct 10, 2026First seen by HOL Aug 25, 2026Material review Sep 28, 2026

Upstream Advisory

Key facts

Risk: Critical · CVSS 9.3
Exploitation: Not marked as known exploited
Affected software: 2 mapped packages or products
Fix availability: Not reported

Why this deserves its current priority

CVSS is 9.3. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.

Analysis status

Analysis pending evidence review

Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.

Affected scope and exposure questions

The current feed maps TYPO3/Extension "HTML5 Video Player vs. Powermail" (generic), TYPO3/lochmueller/html5videoplayer-powermail (generic). Check affected ranges and fixed versions before updating.

Mapped affected packages and fixed versions
Package	Affected range	Fixed version
TYPO3/Extension "HTML5 Video Player vs. Powermail"generic	0	Not reported
TYPO3/lochmueller/html5videoplayer-powermailgeneric	>=0 <=0.2.1	Not reported

Recommended response

Check inventory. Check lockfiles and deployed manifests for TYPO3/Extension "HTML5 Video Player vs. Powermail", TYPO3/lochmueller/html5videoplayer-powermail.
Review the reported fix. Monitor this advisory for an available fix and review any installs of the affected package.

Evidence timeline and material changes

Published upstream
Aug 25, 2026
Evidence: source:cvelist:source_dates:source-dates:record
Source modified
Sep 28, 2026
Evidence: source:cvelist:source_dates:source-dates:record
First seen by HOL
Aug 25, 2026

Sources and claim methodology

Source referencetypo3.org

Upstream source description

The extension fails to safely process untrusted client input of an attacker-controlled cookie directly to PHP's unserialize(). A remote, unauthenticated attacker can supply a crafted serialized payload to trigger PHP Object Injection, leading to Remote Code Execution on the TYPO3 server.

Quoted source text, attributed separately from HOL analysis.