7.5

CVE-2026-109869: nodejs undici Uncaught Exception

CVSS: 7.5v3.1HighAnalyzed
AliasesDEBIAN-CVE-2026-109869UBUNTU-CVE-2026-109869
Published 15-10-2026Last modified 16-10-2026
Open JSON

Vulnerability summary

CVE-2026-109869 is a high (CVSS 7.5) Uncaught Exception vulnerability in nodejs undici. EPSS estimates a 0.34% chance of exploitation in the next 30 days, higher than 26.3% of scored vulnerabilities.

Overall risk
30/100
0100
Medium · default modelHow is this calculated?
CVSS score
7.5/10
010
High · v3.1 (CVE.org)
EPSS score
0.34%
0%100%
Low · Change unavailable
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded

Timeline

  1. 15-10-2026
    PublishedVulnerability first disclosed.
  2. 16-10-2026
    Last modifiedVulnerability information updated.

Description

undici is an HTTP client library for Node.js. In versions 6.23.0 through 6.29.0, 7.18.0 through 7.30.0, and 8.0.0 through 8.12.1, its fetch() implementation crashes the Node.js process when a malicious server returns a response with more than five content codings and closes the connection before sending the body. undici rejects such responses because of a content-encoding limit, but it created the internal response stream before that check and returned without attaching an error listener or aborting the request, so the early close surfaces a content-length mismatch on the orphaned stream, which Node.js treats as an unhandled error and terminates the process. A remote, unauthenticated server can trigger this with a single response, even when the application correctly catches the fetch() rejection, resulting in a denial of service. The issue is fixed in undici 6.29.1, 7.30.1, and 8.12.2, and users should upgrade to one of those versions or later. There is no workaround.

CVSS metrics

4 scores · 4 sources · 1 version

EPSS trend

Probability

0.34%

Chance of exploitation in the next 30 days

Percentile

26%

Versus all other CVEs

30-day change

Change unavailable

Change unavailable

16-10-202619-10-2026
EPSS score
0.34%

Known exploited

Compare KEV catalogs

Not in any of the 3 tracked catalogs.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

Debian1 product
  • node-undiciAll versions (No fix recorded)
Nodejs1 product
  • undici≥ 6.23.0, < 6.29.1 | ≥ 7.18.0, < 7.30.1 | ≥ 8.0.0, < 8.12.2
Ubuntu1 product
  • node-undiciAll versions (No fix recorded)
Undici1 product
  • undici≥ 6.23.0, < 6.29.1 | ≥ 7.18.0, < 7.30.1 | ≥ 8.0.0, < 8.12.2

4 vendors · 4 products

References

5 links