Vulnerability-Lookup

CVE-2026-85024 (GCVE-0-2026-85024)

Vulnerability from cvelistv5 – Published: 2026-09-04 16:20 – Updated: 2026-09-04 19:30

Title

undici vulnerable to Denial of Service via unhandled error in WebSocket permessage-deflate decompression

Summary

undici bundles a WebSocket client whose permessage-deflate size-limit cleanup removes all listeners from the internal zlib inflate stream, including its error listener, while that stream can still emit. When a remote peer sends a compressed payload that crosses the built-in 128 MiB decompressed-payload limit and then contains a malformed DEFLATE byte, the inflate stream emits a data error with no listener attached, which Node.js treats as a fatal unhandled error and terminates the entire process. Exploitation is remote and unauthenticated, requires no application mistake, and is asymmetric, since roughly 130 KB on the wire expands past the limit and crashes the process, and reconnecting can repeat the crash. This affects undici versions from 6.25.0 up to 6.28.1, from 7.28.0 up to 7.29.1, and from 8.1.0 up to 8.10.2. Users should upgrade to undici 6.28.1, 7.29.1, or 8.10.2.

Severity

5.9 (Medium)


                        
                          CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H

SSVC

Exploitation: none Automatable: no Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-09-04 19:30 UTC

CWE

CWE-248 - Uncaught Exception

Assigner

openjs redhat root

References

2 references

URL	Tags
https://github.com/nodejs/undici/security/advisor…
https://cna.openjsf.org/security-advisories.html

Impacted products

1 product

Vendor	Product	Version	CPE status
undici	undici	Affected: 6.25.0 , < 6.28.1 (semver) Unaffected: 6.28.1 (semver) Affected: 7.28.0 , < 7.29.1 (semver) Unaffected: 7.29.1 (semver) Affected: 8.1.0 , < 8.10.2 (semver) Unaffected: 8.10.2 (semver)	guessed

Credits

mcollina krsecu UlisesGascon

Show details on NVD website

JSON

To clipboard

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FKIE_CVE-2026-85024

Vulnerability from fkie_nvd - Published: 2026-09-04 17:17 - Updated: 2026-09-04 20:17

Severity

5.9 (Medium) - CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H

Summary

References

	URL	Tags
	ce714d77-add3-4f53-aff5-83d477b104bb	https://cna.openjsf.org/security-advisories.html
	ce714d77-add3-4f53-aff5-83d477b104bb	https://github.com/nodejs/undici/security/advisories/GHSA-3wwx-pv8p-q78v

Impacted products

	Vendor	Product	Version

JSON

To clipboard

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          "defaultStatus": "unaffected",
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          "product": "undici",
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}

Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Detection rules are retrieved from Rulezet.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.

Action not permitted

CVE-2026-85024 (GCVE-0-2026-85024)

FKIE_CVE-2026-85024

Tags

Sightings

Nomenclature