Affected versions: ≥ 2.0.2 and < 2.0.3
Full advisory: our disclosure post
CVE-2026-67284MediumCVSS 5.3
Cotton Cloud (com_cotton) 2.0.2 - Authenticated Access to Every Other User's Files
Cotton Cloud 2.0.2 fixed the unauthenticated access covered by CVE-2026-67283 but left the underlying authorisation flaw in place. The by-id database accessors fetch files and folders by their numeric id with no check that the id belongs to the caller, so any authenticated user can read, overwrite, delete and re-assign permissions on files owned by any other user. On a site with open user registration, which is the normal setup for a file store, a free account is enough. The component also sets the response content type from the file extension, so an attacker can plant an HTML file that serves script from the site's own origin. CVSS 4.0 5.3 MEDIUM (AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:L/VA:N), CWE-284. Update to Cotton Cloud 2.0.3 or later. Reported by Phil Taylor of mySites.guru.
Affected versions: ≥ 2.0.2 and < 2.0.3
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-2026-67284 is scored
The base metrics as Joomla CNA 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.
5.3 Medium
CVSS 4.0, scored by Joomla CNACVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:NHow it is reached
- AV:N Attack vector
- Network. Reachable across the internet
- AC:L Attack complexity
- Low. Nothing to work around, it just works
- AT:N Attack requirements
- None. Works against any affected install
- PR:L Privileges required
- Low. Any logged-in account will do
- UI:N User interaction
- None. Nobody has to be tricked into anything
What it does to the site
- VC:L Confidentiality
- Low. Some data can be read
- VI:L Integrity
- Low. Some data can be altered
- VA:N Availability
- None. The site stays up
What it does beyond the site
- SC:N Confidentiality
- None. Other systems keep their data
- SI:N Integrity
- None. Other systems keep their integrity
- SA:N Availability
- None. Other systems stay up
Affected extensions and versions
Our disclosure post
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Rules current as of 21 September 2026.