Vulnerability record

CVE-2020-17496

vBulletin PHP Module Remote Code Execution Vulnerability

CriticalExploitation confirmedCISA KEV

What should I do?

This vulnerability is in the CISA Known Exploited Vulnerabilities catalog: attackers are using it. If you run vBulletin, fix it now.

CISA required action: Apply updates per vendor instructions.

US federal civilian agencies must remediate by May 3, 2022.

Patch status

Official fix available since Sep 30, 2026

Apply the vendor's update to every affected system. Check the fixed-in versions below where known.

Basis: NVD patch reference

Patch or advisory on forum.vbulletin.com (opens in a new tab)

Description

vBulletin 5.5.4 through 5.6.2 allows remote command execution via crafted subWidgets data in an ajax/render/widget_tabbedcontainer_tab_panel request. NOTE: this issue exists because of an incomplete fix for CVE-2019-16759.

Source: NIST National Vulnerability Database. Official vulnerability data, reproduced as published.

Affected products

Products affected by this vulnerability, with versions and the source of each entry
Product	Vendor	Affected versions	Source
vBulletin	vBulletin	>= 5.5.4, <= 5.6.2	KEV

Sources: KEV = CISA Known Exploited Vulnerabilities catalog.

Intelligence timeline

Developments from the last 30 days, newest first.

CVSS scoredUpdateKEVSep 30, 2026
CVE-2020-17496 scored CVSS 9.8: vBulletin vBulletin, vBulletin PHP Module Remote Code Execution Vulnerability
CISA lists this as exploited in the wild. Unpatched vBulletin systems are exposed to active attacks now.
Basis: NIST National Vulnerability Database
Patch releasedUpdateKEVSep 30, 2026
Patch released for CVE-2020-17496: vBulletin vBulletin, vBulletin PHP Module Remote Code Execution Vulnerability
An official fix is now available for vBulletin vBulletin. This vulnerability is being exploited, so apply it promptly.
Basis: NVD patch reference

1 earlier event is available with a subscription. See plans.

Coverage

We have not published a story about this vulnerability yet.

References

nvd.nist.gov https://nvd.nist.gov/vuln/detail/CVE-2020-17496
blog.exploitee.rs https://blog.exploitee.rs/2020/exploiting-vbulletin-a-tale-of-patch-fail/
cwe.mitre.org https://cwe.mitre.org/data/definitions/78.html
forum.vbulletin.com https://forum.vbulletin.com/forum/vbulletin-announcements/vbulletin-announcements_aa/4445227-vbulletin-5-6-0-5…
seclists.org https://seclists.org/fulldisclosure/2020/Aug/5
cisa.gov https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2020-17496