CVE-2026-26226Public exploitNetwork attack vector

Cross-site scripting via unescaped SVG style attributes

Published Feb 13, 2026 · Updated Feb 13, 2026

Cross-site scripting in Luki Labs beautiful-mermaid before 0.1.3 allows remote attackers to execute script via crafted Mermaid diagrams. The SVG renderer interpolates fill, stroke, stroke-width, and color values from style and classDef directives into attributes without XML escaping. A consuming application must render attacker-controlled input and embed the resulting SVG in a web page, where execution occurs within the embedding origin.

CVSS severity5.3
Medium
EPSS probability0.52%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Cross-site scripting in Luki Labs beautiful-mermaid before 0.1.3 allows remote attackers to execute script via crafted Mermaid diagrams. The SVG renderer interpolates fill, stroke, stroke-width, and color values from style and classDef directives into attributes without XML escaping. A consuming application must render attacker-controlled input and embed the resulting SVG in a web page, where execution occurs within the embedding origin.

The record

CVE
CVE-2026-26226
Published
Feb 13, 2026
Updated
Feb 13, 2026
Vendor
Luki Labs
Product
beautiful-mermaid
Classifications
CWE-79, T1203
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Feb 13, 2026CVE publishedPublication date reported by the CVE source.
  2. Feb 13, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=0 <0.1.3

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Luki Labs · beautiful-mermaidversion=0 <0.1.3

Published CVSS scores

5.3VulnCheckCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:L/VI:L/VA:N/SC:L/SI:L/SA:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-79Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
T1203Exploitation for Client Execution

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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