critical Known exploitedREV. 01

CVE-2019-16759vBulletin — Code Execution via a Widget Parameter

The vBulletin forum software evaluates a request parameter as code, so an unauthenticated visitor takes over any affected forum with a single request.

YOUR NEXT MOVE

Upgrade vBulletin past 5.5.4, and rebuild forums that were reachable while unpatched.

Read the risk

THE VITAL STATS
CVSS score
9.8/ 10
CVSS v3.1
EPSS probability
100%
Likelihood of exploitation
Attack complexity
Low
Conditions needed to exploit
Known exploited
Yes — CISA KEV
CVE published
2019-09-24
Added to KEV
2021-11-03
Exploit published
Yes
Confidence
high
Kill chain
initial access
MITRE ATT&CK
T1190, T1059
Severity
critical

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Attacker needsNetwork access to the forum

Behind the card

5 REFERENCES
Field-level provenanceTRACE THE SOURCES +

Which source supports each field, when it was retrieved, and who extracted it.

FieldsSourceRetrievedExtractorConfidence
cvss, exploitation.attack_complexity, exploitation.exploit_available, references, published_atnvd.nist.gov2026-08-07scrty-crds-pipeline/0.1high
exploitation.known_exploited, exploitation.kev_addedcisa.gov2026-08-07scrty-crds-pipeline/0.1high
epssapi.first.org2026-08-07scrty-crds-pipeline/0.1high
title, summary, severity, remediation, mitre_attack, kill_chain, recommended_action, confidence, tags, exploitation.prerequisitesnvd.nist.gov2026-08-07claude-codehigh

Printing history

THE RECORD
  1. r1Initial base card

First printing. This card has not been reprinted since publication.

crds:cve-2019-16759 · CRDS 0.1 · Issued 2026-08-07