CVE-2026-28556: wpForo Forum 2.4.14 Missing Authorization via Topic Management Form Handlers

Severity: medium (CVSS 5.4 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.3% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-02-28 · updated 2026-06-17
Weakness: CWE-862

Description

wpForo Forum 2.4.14 contains a missing authorization vulnerability that allows authenticated subscribers to move, merge, or split any forum topic via the topic_move, topic_merge, and topic_split form action handlers. Attackers with a valid form nonce can reorganize arbitrary forum content without moderator permissions, including relocating topics to private forums.

Affected products

tomdever wpForo Forum: from 2.4.0 before 2.4.16 — fixed in 2.4.16

How to fix

Upgrade to a fixed version: tomdever wpForo Forum 2.4.16. Check the vendor advisory for mitigations.

References

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