CVE-2026-52807 Gogs: DOM-based XSS via Milestone Name on New Issue Page
An attacker can execute arbitrary JavaScript in a victim's browser by storing a malicious payload in a milestone name within the Gogs Git service.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- A user has to click or open something
- Fix
- Available
What is CVE-2026-52807?
CVE-2026-52807 is a medium-severity cross-site scripting vulnerability in gogs, published on 24 Jun 2026. Any signed-in user can exploit it over the network, and only if a user opens a file or follows a link.
Official description
Gogs is an open source self-hosted Git service. Prior to 0.14.3, in new_form.tmpl, milestone names are rendered with Go's default auto-escaping ({{.Name}}), which converts < to < etc. This prevents direct HTML injection. However, when the browser renders the DOM, the text content of the element contains the decoded original payload. Semantic UI 2.4.2's dropdown component has preserveHTML: true as the default setting. When a user selects a dropdown item, the internal set.text() method calls jQuery's .html() with the item's text content. This re-parses the decoded text as HTML, creating the injected element and triggering the JavaScript event handler. An attacker can store an HTML/JavaScript payload in a milestone name, and when any user opens the New Issue page and interacts with the milestone dropdown, the payload executes in their browser via Semantic UI's preserveHTML behavior. This vulnerability is fixed in 0.14.3.
Weakness: CWE-79
Which versions are affected by CVE-2026-52807?
3 open source packages ship an affected version, including gogs.io/gogs.
| Package | Affected | Fixed in |
|---|---|---|
gogs.io/gogs Go | All versions | None |
gogs.io/gogs Go | All versions | 0.14.3 |
gogs.io/gogs Go | All versions | 0.14.3 |
How do I fix CVE-2026-52807?
Upgrade gogs.io/gogs to 0.14.3 or later.
Escape output for the context it lands in and set a strict Content Security Policy. Upgrading the affected component is the real fix. More about Cross-site scripting.
Is CVE-2026-52807 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-52807 exists.
Sources
Also known as GHSA-vcm5-gvmp-78mp, GO-2026-5661.