CVE-2026-81753

Flowintel Stored XSS in Case Notes via Malicious Mermaid Diagram Content

MEDIUM
5.1
CVSS Score
Published: August 27, 2026 at 12:06 PM UTC
Updated: August 28, 2026 at 03:42 PM UTC
1 product affected across 1 vendorFlowintel

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Severity
MEDIUM5.1
Exploit prediction
EPSS 0.5%
SSVC
No known exploit

Description

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

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

v ≤ 3.3.0

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

SSVC — Action Prioritization

SSVCNo known exploitNot automatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

5.1MEDIUMCIRCL
Vector?

Quick Info

StatusDEFERRED
CWE
CWE-79

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