CVE-2026-81753Flowintel Stored XSS in Case Notes via Malicious Mermaid Diagram Content

Affected versions of Flowintel render Mermaid blocks contained in stored case notes without sufficiently neutralizing attacker-controlled markup. Because Mermaid note content is persisted and later rendered for other users, an attacker with permission to create or edit a note could store a crafted Mermaid payload that results in JavaScript execution when another user views the affected case note. The patch adds explicit Mermaid detection and HTML escaping around the token content before the generated Mermaid wrapper is returned. It also moves the wrapping logic earlier in page initialization so Markdown instances are protected consistently. Version impacted >= 3.3.0

CVSS

5.1 MEDIUM (v4.0, CNA)CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:L/VI:L/VA:N/SC:L/SI:L/SA:N

Weakness (CWE)

CWE-79

Known exploited

Not in CISA's KEV catalog

EPSS (exploitation in the next 30 days)

Not loaded for this CVE

Assigned by

CIRCL

NVD analysis

Deferred

Record last updated

Aug 27, 2026

First seen by InfoSec Signals

Oct 9, 2026

The CVE record on cve.org · NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.