decode-uri-component: Denial of service via quadratic replacement of percent-encoded runs (SamVerschueren decode-uri-component)

CVE-2026-118664
HIGH 8.2

At a glance

Source
CVE.org
EPSS
EPSS 0.32 % · percentile 25 ()
State
PUBLISHED
Published
Updated
Assigner
GitHub_M

Description

decode-uri-component provides a more robust alternative to decodeURIComponent. Prior to 0.5.1, decodeUriComponent in index.js falls back to customDecodeURIComponent after native decoding throws, and the fallback collects every distinct percent-encoded run before performing a full-string regular-expression replacement for each entry. Malformed input containing many distinct runs can therefore make both the number of replacements and the scanned input length grow together, causing quadratic CPU consumption and blocking the Node.js event loop; request-body inputs can reach the demonstrated size, while ordinary URL header limits reduce the practical delay. This issue is fixed in version 0.5.1.

Weaknesses (CWE)

  • CWE-400 — Uncontrolled Resource Consumption
  • CWE-407 — Inefficient Algorithmic Complexity

References

Scores

VersionScoreVectorScored by
CVSS 4.0HIGH 8.2CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:NGitHub_M

European references

Affected products

ProductVersions
SamVerschueren · decode-uri-componentaffected < 0.5.1

Sources

SourceLicence
CVE List (CVEProject cvelistV5)CVE Program Terms of Use
EPSS (FIRST.org)FIRST — attribution requested
ENISA EUVDENISA — reproduction authorised, source acknowledged