Node.js Undici up to 7.29.0/8.10.1 Dump Interceptor input validation

Summaryinfo

A vulnerability identified as problematic has been detected in Node.js Undici up to 7.29.0/8.10.1. The impacted element is an unknown function of the component Dump Interceptor. The manipulation leads to input validation. This vulnerability is referenced as CVE-2026-84947. Remote exploitation of the attack is possible. No exploit is available.

Detailsinfo

A vulnerability was found in Node.js Undici up to 7.29.0/8.10.1 and classified as problematic. This issue affects some unknown functionality of the component Dump Interceptor. The manipulation with an unknown input leads to a input validation vulnerability. Using CWE to declare the problem leads to CWE-20. The product receives input or data, but it does not validate or incorrectly validates that the input has the properties that are required to process the data safely and correctly. Impacted is integrity. The summary by CVE is:

undici's dump interceptor reads and discards a response body up to a configurable maximum size. When a response declares a Content-Length that exceeds the maximum, the interceptor aborts cleanly, but when a response has no Content-Length and is chunked, the interceptor instead signals completion early once the accumulated size reaches the maximum, without pausing or aborting the request. Because the underlying parser keeps delivering body bytes, a second completion signal fires and trips an internal assertion, which aborts the request and tears down the connection. The application is left observing a misleading successful status with an empty or truncated body while the connection has actually been disconnected. This affects undici versions from 7.1.0 up to 7.29.1 and from 8.0.0 up to 8.10.2. Users should upgrade to undici 7.29.1 or 8.10.2.

The advisory is shared at github.com. The identification of this vulnerability is CVE-2026-84947 since 09/02/2026. The exploitation is known to be easy. The attack may be initiated remotely. No form of authentication is needed for a successful exploitation. Neither technical details nor an exploit are publicly available.

Upgrading to version 7.29.1 or 8.10.2 eliminates this vulnerability.

The vulnerability is also documented in the vulnerability database at EUVD (EUVD-2026-71517). Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

Type

• JavaScript Library

Vendor

• Node.js

Name

• Undici

Version

• 7.0
• 7.1
• 7.2
• 7.3
• 7.4
• 7.5
• 7.6
• 7.7
• 7.8
• 7.9
• 7.10
• 7.11
• 7.12
• 7.13
• 7.14
• 7.15
• 7.16
• 7.17
• 7.18
• 7.19
• 7.20
• 7.21
• 7.22
• 7.23
• 7.24
• 7.25
• 7.26
• 7.27
• 7.28
• 7.29.0
• 8.10.0
• 8.10.1

License

• open-source

CPE 2.3info

• 🔒
• 🔒
• 🔒

CPE 2.2info

• 🔒
• 🔒
• 🔒

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CVSSv3info

CVSSv2info

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Entryinfo

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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