Mermaid is a JavaScript tool that uses Markdown-inspired text to create and modify diagrams and charts. Prior to 10.9.6 and 11.15.0, there is a denial-of-service attack when rendering gantt charts, if they use the excludes attribute to exclude all dates. mermaid.parse is unaffected, unless you then call the ganttDb.getTasks() (which is called when rendering a diagram). This vulnerability is fixed in 10.9.6 and 11.15.0.

Affected: npm: mermaid

### Impact

Mermaid v11.14.0 and earlier are vulnerable to a denial-of-service attack when rendering gantt charts, if they use the [`excludes` attribute](https://mermaid.js.org/syntax/gantt.html?#excludes) to exclude all dates.

Example:

``` gantt excludes monday,tuesday,wednesday,thursday,friday,saturday,sunday DoS :2025-01-01, 1d ```

`mermaid.parse` is unaffected, unless you then call the `ganttDb.getTasks()` (which is called when rendering a diagram).

### Patches

This has been patched in:

- [v11.15.0](https://github.com/mermaid-js/mermaid/releases/tag/mermaid%4011.15.0) (see [faafb5d49106dd32c367f3882505f2dd625aa30e](https://github.com/mermaid-js/mermaid/commit/faafb5d49106dd32c367f3882505f2dd625aa30e)) - [v10.9.6](https://github.com/mermaid-js/mermaid/releases/tag/v10.9.6) (see [a59ea56174712ee5430dfd5bc877cb5151f501a6](https://github.com/mermaid-js/mermaid/commit/a59ea56174712ee5430dfd5bc877cb5151f501a6))

### Workarounds

There are no workarounds available without updating to a newer version of mermaid.

Affected: Ubuntu:22.04:LTS: node-mermaid

Mermaid is a JavaScript tool that uses Markdown-inspired text to create and modify diagrams and charts. Prior to 10.9.6 and 11.15.0, there is a denial-of-service attack when rendering gantt charts, if they use the excludes attribute to exclude all dates. mermaid.parse is unaffected, unless you then call the ganttDb.getTasks() (which is called when rendering a diagram). This vulnerability is fixed in 10.9.6 and 11.15.0.