CVE-2026-26226
beautiful-mermaid contains an SVG attribute injection issue that can lead to cross-site scripting (XSS)
Impact
beautiful-mermaid versions prior to 0.1.3 contain an SVG attribute injection issue that can lead to cross-site scripting (XSS) when rendering attacker-controlled Mermaid diagrams. User-controlled values from Mermaid style and classDef directives are interpolated into SVG attribute values without proper escaping, allowing crafted input to break out of an attribute context and inject arbitrary SVG elements/attributes into the rendered output. When the generated SVG is embedded in a web page, this can result in script execution in the context of the embedding origin.
Affected packages
| Ecosystem | Package | Affected | Fixed in |
|---|---|---|---|
| npm | beautiful-mermaid | < 0.1.3 | 0.1.3 |
Affected products
| Product | Affected versions |
|---|---|
| Beautiful-Mermaid | before 0.1.3 |
Versions were read from the advisory text. No structured product data has been published for this record yet.
Weakness classification
References
- NVD record
- CVE.org record
- GitHub advisory
- https://github.com/lukilabs/beautiful-mermaid/pull/8
- https://github.com/lukilabs/beautiful-mermaid/releases/tag/v0.1.3
- https://neo.projectdiscovery.io/share/cec71dc7-a8eb-417e-b8b4-666644796c1e
- https://www.vulncheck.com/advisories/beautiful-mermaid-svg-attribute-injection
- https://github.com/advisories/GHSA-cgmm-x5ww-q5cr
- https://nvd.nist.gov/vuln/detail/CVE-2026-26226
- https://github.com/lukilabs/beautiful-mermaid/commit/68f3ab8c9658e7f4a3b749e06a6b96e4c3f55db1