CVE-2026-118664：decode-uri-component 造成二次方 CPU 消耗的拒絕服務漏洞
CVE-2026-118664 - decode-uri-component: Denial of service via quadratic replacement of percent-encoded runs
decode-uri-component 在 0.5.1 之前因處理百分號編碼方式不當，會導致二次方 CPU 消耗，進而阻塞 Node.js 事件迴圈，形成拒絕服務漏洞。
此 CVE 說明了在 decode-uri-component 0.5.1 之前的實現會因大量百分號編碼導致二次方 CPU 消耗，提示開發者及時升級以避免服務中斷。
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.
Impact
Affected Products
The following products are affected by CVE-2026-118664
vulnerability.
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No affected product recoded yet
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 4.0 | HIGH | [email protected] |
Update decode-uri-component to version 0.5.1 or later to fix quadratic CPU consumption.
- Update the decode-uri-component library to version 0.5.1 or newer.
- Test the application for performance degradation.
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Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
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New CVE Received by [email protected]
十月. 28, 2026
Action Type Old Value New Value Added 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. Added CVSS V4.0 AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X Added CWE CWE-407 Added CWE CWE-400 Added Affected New affected value received. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/118xxx/CVE-2026-118664.json">CVE-2026-118664</a> Added Reference https://github.com/SamVerschueren/decode-uri-component/commit/fad01d65b93bd3f2f0dc32dfd8d57a38b57bc608 Added Reference https://github.com/SamVerschueren/decode-uri-component/releases/tag/v0.5.1 Added Reference https://github.com/SamVerschueren/decode-uri-component/security/advisories/GHSA-qr28-fpjm-wq7f
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