CVE catalog

CVE-2026-84947

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

[CVE catalog]

Severity: Medium · CVSS 6.5CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:H
Published: Aug 12, 2026, 2:18:37 PM UTC
Updated: Sep 4, 2026, 5:17:02 PM UTC
Source: [NVD] · [CVE record]
EPSS: 0.20% · Oct 25, 2026

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.

Vulnerable and fixed packages

Distribution-reported package versions and fixes. These do not depend on matching against the OpenFactory package catalog.

Distribution	Package	Release	Version	Status
Debian	node-undici	sid	`8.12.2+dfsg+~cs3.2.3-2`	fixed
Debian	node-undici	forky	`8.10.2+dfsg+~cs3.2.2-1`	fixed
Debian	node-undici	trixie	`7.3.0+dfsg1+~cs24.12.11-1`	vulnerable
Debian	node-undici	bookworm	`5.15.0+dfsg1+~cs20.10.9.3-1+deb12u4`	vulnerable
Debian	node-undici	bookworm-security	`5.15.0+dfsg1+~cs20.10.9.3-1+deb12u3`	vulnerable
Cpe	undici	Not reported	`8.10.2`	fixed
Npm	undici	Not reported	`8.10.2`	fixed

Fixed-version evidence

Distribution	Package	Type	Release	Fixed version	Urgency	Origin	Bugs
Debian	node-undici	source	sid	`8.10.2+dfsg+~cs3.2.2-1`	not yet assigned	Not reported	[1146745]
Debian	node-undici	source	forky	`8.10.2+dfsg+~cs3.2.2-1`	not yet assigned	Not reported	[1146745]
Debian	node-undici	source	trixie	`(unfixed)`	not yet assigned	Not reported	[1146745]
Debian	node-undici	source	bookworm	`(unfixed)`	not yet assigned	Not reported	[1146745]
Cpe	undici	cpe	Not reported	`8.10.2`	Not reported	NVD-CVE-2026-84947	Not reported
Npm	undici	npm	Not reported	`8.10.2`	Not reported	GHSA-2GQQ-GQF2-X968	Not reported

[Debian bug #1146745]

Notes

[trixie] node-undici: Minor issue [bookworm] node-undici: Minor issue

OpenFactory catalog packages

[Debian 12 (Bookworm)]

[node-llhttp]Affected
Source package: [node-undici]
Details (4)
- 8.1.0~5.15.0+dfsg1+~cs20.10.9.3-1+deb12u4 · all · bookworm
  Affected
  nvd · node-undici · debian · bookworm; nvd · node-undici · debian · 12
- 8.1.0~5.15.0+dfsg1+~cs20.10.9.3-1+deb12u4 · all · bookworm
  Affected
  nvd · node-undici · debian · bookworm; nvd · node-undici · debian · 12
- 8.1.0~5.15.0+dfsg1+~cs20.10.9.3-1+deb12u3 · all · bookworm-security
  Affected
  nvd · node-undici · debian · bookworm; nvd · node-undici · debian · 12
- 8.1.0~5.15.0+dfsg1+~cs20.10.9.3-1+deb12u3 · all · bookworm-security
  Affected
  nvd · node-undici · debian · bookworm; nvd · node-undici · debian · 12
[node-undici]Affected
Details (4)
- 5.15.0+dfsg1+~cs20.10.9.3-1+deb12u4 · all · bookworm
  Affected
  nvd · node-undici · debian · bookworm; nvd · node-undici · debian · 12
- 5.15.0+dfsg1+~cs20.10.9.3-1+deb12u4 · all · bookworm
  Affected
  nvd · node-undici · debian · bookworm; nvd · node-undici · debian · 12
- 5.15.0+dfsg1+~cs20.10.9.3-1+deb12u3 · all · bookworm-security
  Affected
  nvd · node-undici · debian · bookworm; nvd · node-undici · debian · 12
- 5.15.0+dfsg1+~cs20.10.9.3-1+deb12u3 · all · bookworm-security
  Affected
  nvd · node-undici · debian · bookworm; nvd · node-undici · debian · 12

[Debian 13 (Trixie)]

[libllhttp9.2]Affected
Source package: [node-undici]
Details (2)
- 9.2.1~7.3.0+dfsg1+~cs24.12.11-1 · amd64 · trixie
  Affected
  nvd · node-undici · debian · 13
- 9.2.1~7.3.0+dfsg1+~cs24.12.11-1 · arm64 · trixie
  Affected
  nvd · node-undici · debian · 13
[libllhttp-dev]Affected
Source package: [node-undici]
Details (2)
- 9.2.1~7.3.0+dfsg1+~cs24.12.11-1 · amd64 · trixie
  Affected
  nvd · node-undici · debian · 13
- 9.2.1~7.3.0+dfsg1+~cs24.12.11-1 · arm64 · trixie
  Affected
  nvd · node-undici · debian · 13
[node-llhttp]Affected
Source package: [node-undici]
Details (2)
- 9.2.1~7.3.0+dfsg1+~cs24.12.11-1 · all · trixie
  Affected
  nvd · node-undici · debian · 13
- 9.2.1~7.3.0+dfsg1+~cs24.12.11-1 · all · trixie
  Affected
  nvd · node-undici · debian · 13
[node-undici]Affected
Details (2)
- 7.3.0+dfsg1+~cs24.12.11-1 · all · trixie
  Affected
  nvd · node-undici · debian · 13
- 7.3.0+dfsg1+~cs24.12.11-1 · all · trixie
  Affected
  nvd · node-undici · debian · 13

Observed: Oct 23, 2026, 9:42:11 PM UTC

References

[CERT-Bund public advisories] · [Debian Security Tracker] · [FIRST EPSS] · [GitHub Advisory Database] · [National Vulnerability Database (NVD)] · [OSV Package Vulnerability Database] · [Red Hat security advisories and VEX] · [SUSE security advisories and VEX]