Machine-written summary
Summary written by Claude Haiku from the source advisory. Not reviewed by a person.
Mercury versions 3.0.0 up to but not including 3.2.11 are affected through the mr.Markdown widget, which renders its input as raw, unsanitized HTML. If an app passes untrusted data such as user submissions or database rows to mr.Markdown, an attacker can supply script that runs in the browser of other users who view the app, and the attacker needs no account on an unauthenticated deployment. Upgrade to version 3.2.11, which is the fixed release.
Not analysed yet
We haven’t published our analysis of this Advisory yet. Once a person has reviewed it, this page will say what’s vulnerable, what has to be true for your app to be affected, and how to check.
Severity and exploitation
| Score | Rating | CVSS | Vector | Source |
|---|---|---|---|---|
| 6.1 | Medium | 3.1 | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N | CNA (GitHub_M) |
- CISA KEV Not listed.
- EPSS 0.0028, the 21st percentile, on 5 Nov 2026: FIRST’s estimate of the chance of exploitation in the next 30 days.
Timeline
- 31 Oct 2026, 14:08 UTC First seen by agentprime
- 31 Oct 2026, 14:08 UTC Confirmed by OSV