CVE-2026-77143

Broken Access Control in extension "Forum" (pforum)

HIGH
8.8
CVSS Score
Published: August 25, 2026 at 09:00 AM UTC
Updated: September 28, 2026 at 11:10 PM UTC
1 product affected across 1 vendorForum

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Severity
HIGH8.8
Exploit prediction
EPSS 0.4%
SSVC
No known exploit

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.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

60%
v < 4.0.45.0.0 ≤ v < 5.0.16.0.0 ≤ v < 6.2.45.0.06.0.0
Affected range stops below 4.0.4, so it looks safe — our inference, not a vendor statement
Affected range stops below 5.0.1, so it looks safe — our inference, not a vendor statement
Affected range stops below 6.2.4, so it looks safe — our inference, not a vendor statement

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

References (1)

SSVC — Action Prioritization

SSVCNo known exploitAutomatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

8.8HIGHTYPO3
Vector?

Quick Info

StatusDEFERRED
CWE
CWE-862CWE-639

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