CVE-2026-52781: OpenProject is open-source, web-based project management software. Prior to 17.3.3 and 17.4.1, the HTML sanitizer grants elements unrestricted data-*…

PriorityP339medium6.4CVSS 3.1

AVNACLPRLUINSCCLILAN

EPSS

0.15%

4.6th percentile

OpenProject is open-source, web-based project management software. Prior to 17.3.3 and 17.4.1, the HTML sanitizer grants elements unrestricted data-* attributes via :data wildcard. An attacker injects data-controller="poll-for-changes" into a work package description, causing Stimulus.js to mount a controller that fetches an attacker-uploaded attachment and passes it to renderStreamMessage(). This executes arbitrary Turbo Stream actions — including redirect_to — in every victim's authenticated browser session, redirecting them to an attacker-controlled server. This vulnerability is fixed in 17.3.3 and 17.4.1.

Affected

2 ranges

Vendor	Product	Version range	Fixed in
opf	openproject	< 17.3.3	17.3.3
opf	openproject	—	—

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