Affected versions: ≥ 16.0.0 and < 17.0.0
Full advisory: regularlabs.com
CVE-2026-88853HighCVSS 7.5Published 13 September 2026
Modals (modals) 16.0.0 to below 17.0.0 - Authenticated Stored XSS via JavaScript URLs and JavaScript Events
Regular Labs Modals 16.0.0 through 16.2.0 is affected by two vendor-confirmed security defects, both fixed in 17.0.0 (released 13 September 2026). CVE-2026-85189: modal links accepted javascript: URLs, so a crafted link executed script when the modal was opened. CVE-2026-88853: JavaScript Events could be attached by any user able to author content; 17.0.0 restricts them to selected article author groups by default. Both require the ability to author or edit content containing Modals links or tags, making this an authenticated stored XSS. Update to 17.0.0 or later. Note that 17.0.0 is flagged by the vendor as a BC BREAK: the JavaScript Events restriction is enabled by default and has to be re-opened deliberately per author group, so review those settings after updating. The CVE records were published on 14 September 2026: CVE-2026-85189 at CVSS 4.0 7.5 (High), vector CVSS:4.0/AV:N/AC:L/AT:P/PR:H/UI:N/VC:H/VI:H/VA:L/SC:N/SI:N/SA:N/S:N/AU:N; CVE-2026-88853 at CVSS 4.0 7.5 (High), vector CVSS:4.0/AV:N/AC:L/AT:P/PR:H/UI:N/VC:H/VI:H/VA:L/SC:N/SI:N/SA:N/S:N/AU:N.
Affected versions: ≥ 16.0.0 and < 17.0.0
Official record: cve.org · NVD
Every connected Joomla site is checked against these rules on each audit, and flagged if it runs an affected version.
How CVE-2026-88853 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.
7.5 High
CVSS 4.0, scored by Joomla CNACVSS:4.0/AV:N/AC:L/AT:P/PR:H/UI:N/VC:H/VI:H/VA:L/SC:N/SI:N/SA:N/S:N/AU: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:P Attack requirements
- Present. Needs a particular deployment or race to line up
- PR:H Privileges required
- High. Needs an account with elevated rights
- UI:N User interaction
- None. Nobody has to be tricked into anything
What it does to the site
- VC:H Confidentiality
- High. Everything the site holds can be read
- VI:H Integrity
- High. Data and files can be altered at will
- VA:L Availability
- Low. The site slows or stutters
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
Modals - Modals (modals) 16.0.0 to below 17.0.0 - Authenticated Stored XSS via JavaScript URLs and JavaScript Events
Regular Labs Modals 16.0.0 through 16.2.0 is affected by two vendor-confirmed security defects, both fixed in 17.0.0 (released 13 September 2026). CVE-2026-85189: modal links accepted javascript: URLs, so a crafted link executed script when the modal was opened. CVE-2026-88853: JavaScript Events could be attached by any user able to author content; 17.0.0 restricts them to selected article author groups by default. Both require the ability to author or edit content containing Modals links or tags, making this an authenticated stored XSS. Update to 17.0.0 or later. Note that 17.0.0 is flagged by the vendor as a BC BREAK: the JavaScript Events restriction is enabled by default and has to be re-opened deliberately per author group, so review those settings after updating. The CVE records were published on 14 September 2026: CVE-2026-85189 at CVSS 4.0 7.5 (High), vector CVSS:4.0/AV:N/AC:L/AT:P/PR:H/UI:N/VC:H/VI:H/VA:L/SC:N/SI:N/SA:N/S:N/AU:N; CVE-2026-88853 at CVSS 4.0 7.5 (High), vector CVSS:4.0/AV:N/AC:L/AT:P/PR:H/UI:N/VC:H/VI:H/VA:L/SC:N/SI:N/SA:N/S:N/AU:N.
Affected versions: ≥ 16.0.0 and < 17.0.0
Full advisory: regularlabs.com
Modals - Modals (modals) 16.0.0 to below 17.0.0 - Authenticated Stored XSS via JavaScript URLs and JavaScript Events
Regular Labs Modals 16.0.0 through 16.2.0 is affected by two vendor-confirmed security defects, both fixed in 17.0.0 (released 13 September 2026). CVE-2026-85189: modal links accepted javascript: URLs, so a crafted link executed script when the modal was opened. CVE-2026-88853: JavaScript Events could be attached by any user able to author content; 17.0.0 restricts them to selected article author groups by default. Both require the ability to author or edit content containing Modals links or tags, making this an authenticated stored XSS. Update to 17.0.0 or later. Note that 17.0.0 is flagged by the vendor as a BC BREAK: the JavaScript Events restriction is enabled by default and has to be re-opened deliberately per author group, so review those settings after updating. The CVE records were published on 14 September 2026: CVE-2026-85189 at CVSS 4.0 7.5 (High), vector CVSS:4.0/AV:N/AC:L/AT:P/PR:H/UI:N/VC:H/VI:H/VA:L/SC:N/SI:N/SA:N/S:N/AU:N; CVE-2026-88853 at CVSS 4.0 7.5 (High), vector CVSS:4.0/AV:N/AC:L/AT:P/PR:H/UI:N/VC:H/VI:H/VA:L/SC:N/SI:N/SA:N/S:N/AU:N.
Affected versions: ≥ 16.0.0 and < 17.0.0
Full advisory: regularlabs.com
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Rules current as of 3 October 2026.