High severity · published Aug 25, 2026
CVE-2026-77143
Broken Access Control in extension "Forum" (pforum)
8.8
CVSS
0.4%
EPSS
No
On KEV
Description
The frontend topic editing flow does not verify on the server side that the requesting visitor owns the topic being modified. As a result, a visitor who knows the identifier of a topic from the public forum can submit a modified update request for that topic directly and overwrite its content, without the application confirming ownership. Topic identifiers are visible in the public forum listing, and exploitation requires no privileged access or non-default configuration.
Exploitation
Is it being used?
Exploit prediction (EPSS)0.4% · higher than 35% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
EF
Extension "Forum" · TYPO3
6.0.0 before 6.2.4; 5.0.0 before 5.0.1; before 4.0.4 · source: vendor