Affected versions: ≥ 7.0.0 and < 8.19.6
Full advisory: our disclosure post
CVE-2026-78071HighCVSS 7.5Published 28 August 2026
DPCalendar (com_dpcalendar) 7.0.0 to 8.19.5 (Joomla 3) - Authenticated Stored Cross-Site Scripting
DPCalendar renders a calendar location title into a data-title HTML attribute without escaping it, giving a stored cross-site scripting flaw. A payload such as x" onmouseover="alert(1) has no HTML tags, so it passes through the filterText input filter unchanged and breaks out of the attribute on output, where it becomes a live event handler. Storing the payload requires an account with DPCalendar location create permission (CVSS 4.0 vector PR:H), but the script then runs in the browser of every visitor who views that location page, so the permission bounds who can plant it and not who it hits. This was reported in two stages. Toan Le found the original as vendor issue 12203, fixed on 2026-08-27 in 8.19.5 and 10.12.0, which escaped nine of the ten data-title sinks in the component. mySites.guru proved the same day that the tenth was still open, at components/com_dpcalendar/site/tmpl/location/default_map.php line 23, reported it to Digital Peak and the Joomla Security Strike Team, and Digital Peak confirmed it on 2026-08-28. That last sink was closed on 2026-09-10 in 8.19.6 and 10.12.1, along with seven identical sinks in the free mod_dpcalendar_upcoming module templates (blog, default, horizontal, icon, panel, simple and timeline). CVE-2026-78071 was updated on 2026-09-10 to widen its affected range to 7.0.0-8.19.5 and 9.0.0-10.12.0 and to credit both finders. On Joomla 3 the fixed version is 8.19.6, which is a security-only release containing this one change. If you have overridden the DPCalendar location templates, the unescaped output is still in your override and updating the extension will not reach it.
Affected versions: ≥ 7.0.0 and < 8.19.6
Official record: cve.org · NVD
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How CVE-2026-78071 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
DPCalendar - DPCalendar (com_dpcalendar) 9.0.0 to 10.12.0 (Joomla 4 to 6) - Authenticated Stored Cross-Site Scripting
DPCalendar renders a calendar location title into a data-title HTML attribute without escaping it, giving a stored cross-site scripting flaw. A payload such as x" onmouseover="alert(1) has no HTML tags, so it passes through the filterText input filter unchanged and breaks out of the attribute on output, where it becomes a live event handler. Storing the payload requires an account with DPCalendar location create permission (CVSS 4.0 vector PR:H), but the script then runs in the browser of every visitor who views that location page, so the permission bounds who can plant it and not who it hits. This was reported in two stages. Toan Le found the original as vendor issue 12203, fixed on 2026-08-27 in 8.19.5 and 10.12.0, which escaped nine of the ten data-title sinks in the component. mySites.guru proved the same day that the tenth was still open, at components/com_dpcalendar/site/tmpl/location/default_map.php line 23, reported it to Digital Peak and the Joomla Security Strike Team, and Digital Peak confirmed it on 2026-08-28. That last sink was closed on 2026-09-10 in 8.19.6 and 10.12.1, along with seven identical sinks in the free mod_dpcalendar_upcoming module templates (blog, default, horizontal, icon, panel, simple and timeline). CVE-2026-78071 was updated on 2026-09-10 to widen its affected range to 7.0.0-8.19.5 and 9.0.0-10.12.0 and to credit both finders. Update to 10.12.1 on Joomla 4, 5 and 6. The 9.x line has no patch of its own, so sites there need the staged upgrade across to 10.12.1 rather than a point update. If you have overridden the DPCalendar location templates, the unescaped output is still in your override and updating the extension will not reach it.
Affected versions: ≥ 9.0.0 and < 10.12.1
Full advisory: our disclosure post
Our disclosure post
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Rules current as of 2 October 2026.