Affected versions: ≤ 12.2.8
Full advisory: regularlabs.com
CVE-2026-64796CriticalCVSS 9.8
Sourcerer (sourcerer) below 13.0.0 - Code Execution (CVE-2025-22204) and PHP/Script Privilege Escalation
Regular Labs Sourcerer is affected by two lines of security issue. (1) CVE-2025-22204: improper control of code generation leading to code execution in versions before 11.0.0. (2) The coordinated Regular Labs security release of 22 July 2026 (Sourcerer 13.0.0) restricts PHP in articles to content created and last modified by Super Users, enforces the configured CSS/JavaScript/PHP permissions across tags, attributes, files and both article creators and modifiers, restricts PHP includes to the configured include folder, and fixes script/style security checks that missed executable tag variants - collectively a set of privilege-escalation and code/markup-execution hardening fixes. No CVE was assigned to the 22 July issues. Update to Sourcerer 13.0.0 or later. Note: 13.0.0 preserves your existing Pro security settings on update, so review them to opt into the new stricter defaults. CVE ids assigned by the Joomla CNA for this extension in the 22 July 2026 Regular Labs security release: CVE-2026-64796. Sites on this version range are ALSO within the affected range of CVE-2026-74253 (Sourcerer before 16.0.0, CVSS 4.0 10.0 Critical, unauthenticated remote code execution through unverified reflected code, CWE-94, credited to Lukasz Rybak), whose CNA record was re-scoped on 26 August 2026 and now covers 1.0.0 to 15.0.0. Updating to 13.0.0 is therefore no longer sufficient, and neither is 14.x or 15.0.0: the vendor fix for CVE-2026-74253 was incomplete twice and only Sourcerer 16.0.0 (26 August 2026) resolves it. Update to 16.0.0 or later. The Joomla Security Strike Team confirmed active exploitation in the wild from around 19 August 2026. If you cannot update immediately, disable the Sourcerer system plugin, which is the plugin that renders Sourcerer tags.
Affected versions: ≤ 12.2.8
Official record: cve.org · NVD
Every connected Joomla site is checked against this rule on each audit, and flagged if it runs an affected version.
How CVE-2026-64796 is scored
The base metrics as CISA-ADP published them, and what each one means for a site running an affected version. Threat and environmental metrics are left out: they describe a moment or a particular install rather than the flaw.
9.8 Critical
CVSS 3.1, scored by CISA-ADPCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:HHow it is reached
- AV:N Attack vector
- Network. Reachable across the internet
- AC:L Attack complexity
- Low. Nothing to work around, it just works
- PR:N Privileges required
- None. No account needed
- UI:N User interaction
- None. Nobody has to be tricked into anything
- S:U Scope
- Unchanged. Contained to the extension it is in
What it does
- C:H Confidentiality
- High. Everything the site holds can be read
- I:H Integrity
- High. Data and files can be altered at will
- A:H Availability
- High. The site can be taken down
Affected extensions and versions
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Rules current as of 27 September 2026.