How to Fix CVE-2026-28556: wpForo Forum (Bundle Sibling)
By Sai Kiran Pandrala. Last verified: 2026-05-25.
CVE-2026-28556 is a sibling vulnerability in the same vendor advisory as CVE-2026-28554. Apply the same patched build and you close both. The technical detail below is what differs.
| Severity | 5.3 (Medium) |
|---|---|
| Actively exploited? | No public listing in CISA KEV |
| Affected | wpForo Forum 2.4 to <2.4.16 |
| Fixed in | Same patched build as CVE-2026-28554 |
| Type (CWE) | CWE-862: Missing Authorization |
What's different about CVE-2026-28556?
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.
How to fix CVE-2026-28556
Apply the patched build per the primary write-up: How to Fix CVE-2026-28554. All commands, verification steps, and rollback notes for wpForo Forum are listed there.
Frequently asked questions
Does the CVE-2026-28554 patch close CVE-2026-28556?
Yes. Both CVEs are addressed by the same vendor patch. Applying the patched build closes the full bundle.
Is CVE-2026-28556 listed in CISA KEV?
No public KEV listing at the time of this writing.
Where is the official advisory?
See https://wordpress.org/plugins/wpforo/
References
- Official vendor advisory: https://wordpress.org/plugins/wpforo/
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-28556
- CISA KEV catalog: https://www.cisa.gov/known-exploited-vulnerabilities-catalog
- Primary: How to Fix CVE-2026-28554
*Written by Sai Kiran Pandrala. Part of the wpForo Forum bundle. Full procedure at how-to-fix-cve-2026-28554.*