ZeroHour

CVE-2026-72532

mass

Improper ACL checks in Joomla! category webservice endpoints

CVSS 4.0
5.1 medium
EPSS
<1%p9
Published
()
Modified
AI analysis

CVE-2026-72532 is an improper access control (ACL) check in Joomla! Core's webservice (API) endpoints for categories, affecting Joomla 4.0.0 through 5.4.7 and 6.0.0 through 6.1.2. An authenticated API user whose account lacks permission to manage categories can send requests to the category webservice endpoints and create categories anyway; the CVSS vector indicates high required privileges and only low-severity confidentiality and integrity impact. An attacker gains the ability to insert unauthorized categories into the site's content structure, with no availability impact. Any Joomla 4.x, 5.x up to 5.4.7, or 6.x up to 6.1.2 installation is affected, though practical exploitation depends on the webservice API being enabled and reachable. No public proof-of-concept is known, the flaw is not in CISA KEV, and EPSS puts 30-day exploitation probability at about 0.2%, so no exploitation is currently known.

What to do: Update Joomla to a release later than 5.4.7 in the 5.4 series or later than 6.1.2 in the 6.1 series, per the 2026-08-06 core advisory; Joomla 4.x sites should upgrade to a supported 5.x release. As an interim mitigation, disable the category/content webservice plugins or restrict external access to the /api endpoints. After patching, review recently created categories for unauthorized changes.

Affected
Joomla! Core4.0.0 through 5.4.7
Joomla! Core6.0.0 through 6.1.2
Estimated exposure
mass≈1,000,000+ sites running Joomla 4.x–6.1.2 (only the subset with the webservice API plugins enabled is directly exploitable) — Joomla powers roughly 1–2% of CMS-based websites, on the order of a million or more live installations, and all 4.x through 6.1.2 builds carry the vulnerable code, although reachability via the /api category endpoints requires the…

Order-of-magnitude estimate by the model from install counts, market share and public scan data it knows; verify before quoting.

Description

Joomla! Core - [20260806] - Improper ACL checks for category webservice endpoints in Joomla 4.0.0-5.4.7, 6.0.0-6.1.2 - An improper access check allows unauthorized users to create categories via webservices endpoints.

Vendors
joomla
Products
joomla\!
Ecosystems
Joomla
Weakness
CWE-284
Vector
CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

In the news

[20260805] - Core - Improper ACL checks for category webservice endpoints

Joomla fixes CVE-2026-72532, an improper ACL check letting unauthorized users create categories via webservice endpoints, in CMS 5.4.8/6.1.3.

Joomla disclosed an incorrect access control flaw (CVE-2026-72532) in category webservice endpoints, allowing unauthorized users to create categories for inaccessible components. It affects Joomla CMS 4.0.0-5.4.7 and 6.0.0-6.1.2 and is rated moderate impact and severity with low probability. The fix ships in Joomla 5.4.8 and 6.1.3 on 2026-08-18; it was reported by Amin Isayev and Geo.

Joomla Security Centre · 29d agoAdvisoryCVE-2026-72532