๐Ÿ” CVE Alert

CVE-2026-84890

MEDIUM 5.9

undici vulnerable to Denial of Service via unbounded decompression of compressed responses

CVSS Score
5.9
EPSS Score
0.0%
EPSS Percentile
0th

undici's decompress interceptor decompresses response bodies according to the untrusted Content-Encoding header. While the number of content-encoding layers is capped, the total decompressed output size is unbounded and there is no configuration option to limit it. A malicious or faulty upstream can therefore return a small compressed payload, a compression bomb, that expands to hundreds of megabytes or more in client memory, an asymmetric resource consumption that can exhaust memory and crash the process. This affects undici versions from 7.15.0 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.

CWE CWE-770
Vendor undici
Product undici
Published Sep 4, 2026
Last Updated Sep 4, 2026
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CVSS v3 Breakdown

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
Attack Vector
Attack Complexity
Privileges Required
User Interaction
Scope
Confidentiality
Integrity
Availability

Affected Versions

undici / undici
7.15.0 < 7.29.1 8.0.0 < 8.10.2

References

NVD โ†— CVE.org โ†— EPSS Data โ†—
github.com: https://github.com/nodejs/undici/security/advisories/GHSA-3xpg-4rpp-hhhm cna.openjsf.org: https://cna.openjsf.org/security-advisories.html

Credits

mcollina UlisesGascon