Description
decodeUriComponent() takes quadratic time on malformed input that has many distinct percent-encoded runs. A single unauthenticated request of about 224 KB can block the Node.js event loop for about 20 seconds. Version 0.5.0, the release that fixed CVE-2026-45822, is affected.
Recommendation
Update the decode-uri-component package to the latest compatible version. Followings are version details:
- Affected version(s): <= 0.5.0
- Patched version(s): 0.5.1
References
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Start a free scanRelated Issues
- decode-uri-component: Denial of service via exponential decoding of malformed percent-encoded input - CVE-2026-45822
- decode-uri-component vulnerable to Denial of Service (DoS) - CVE-2022-38900
- fast-uri vulnerable to path traversal via percent-encoded dot segments - CVE-2026-6321
- fast-uri vulnerable to mailto header injection via percent-encoded field-name desynchronization - CVE-2026-86818
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See something that needs correcting? Let us knowUpdated October 29, 2026