Prototype Pollution in mithril
Key facts
- Attack vector
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- Privileges required
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- User interaction
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- Attack complexity
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- Impact type
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- Confidentiality · integrity · availability
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- Fix status
- Fixed
No CVSS vector from any source. Fix status from GitHub.
Summary
Affected versions of `mithril`are vulnerable to prototype pollution. The function `parseQueryString` may allow a malicious user to modify the prototype of `Object`, causing the addition or modification of an existing property that will exist on all objects. A payload such as `__proto__%5BtoString%5D=123` in the query string would change the `toString()` function to `123`. ## Recommendation If you are using mithril 2.x, upgrade to version 2.0.2 or later. If you are using mithril 1.x, upgrade to version 1.1.7 or later.
Why it matters now
SSVC decision points
Not available: CISA has not published SSVC decision points for this record.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| — | mithril (npm) | before 1.1.7 | 1.1.7 | Patch available | GHSA-c3px-v9c7-m734 |
| — | mithril (npm) | 2.0.0 to before 2.0.2 | 2.0.2 | Patch available | GHSA-c3px-v9c7-m734 |
- mithril (npm) Vendor— Affected before 1.1.7 Fixed in 1.1.7 Patch available GHSA-c3px-v9c7-m734
- mithril (npm) Vendor— Affected 2.0.0 to before 2.0.2 Fixed in 2.0.2 Patch available GHSA-c3px-v9c7-m734
Remediation
- Fix · GHSA-c3px-v9c7-m734 mithril (npm) Fixed in 1.1.7 Advisory →
- Fix · GHSA-c3px-v9c7-m734 mithril (npm) Fixed in 2.0.2 Advisory →
Timeline
- 2026-10-03 Threatist record created from GHSA-c3px-v9c7-m734
References
Sources
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences