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.
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.
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.
### 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.
EUVD source date text has no stated timezone and is retained without inventing a UTC instant. Related bulletin membership is not an alias, common cause or applicability claim. A missing vector with a zero score is treated as unrated. Complete vendor/product and underlying source evidence remains in the original JSON.
Original publisher date fields
datePublished: May 29, 2026, 1:54:52 PM
dateUpdated: May 29, 2026, 4:17:31 PM
No normalized affected-package data is projected for this source revision. The original publisher record may contain additional product and version evidence; this does not establish that a package is unaffected.
NVD analysis and CPE criteria are source context, not proof that a package or your environment is affected. Complete affected data, logical configurations and SSVC are retained in the original JSON.
The original JSON retains the logical configuration operators, exclusions and version bounds.
No normalized affected-package data is projected for this source revision. The original publisher record may contain additional product and version evidence; this does not establish that a package is unaffected.