Vulnerability-Lookup

CVE-2026-84890 (GCVE-0-2026-84890)

Vulnerability from cvelistv5 – Published: 2026-09-04 17:04 – Updated: 2026-09-04 18:33

Title

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

Summary

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.

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 18:32 UTC

CWE

CWE-770 - Allocation of Resources Without Limits or Throttling

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: 7.15.0 , < 7.29.1 (semver) Unaffected: 7.29.1 (semver) Affected: 8.0.0 , < 8.10.2 (semver) Unaffected: 8.10.2 (semver)	guessed

Credits

mcollina UlisesGascon

Show details on NVD website

JSON

To clipboard

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FKIE_CVE-2026-84890

Vulnerability from fkie_nvd - Published: 2026-09-04 18:18 - Updated: 2026-09-04 19:17

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-3xpg-4rpp-hhhm

Impacted products

	Vendor	Product	Version

JSON

To clipboard

{
  "affected": [
    {
      "affectedData": [
        {
          "defaultStatus": "unaffected",
          "packageURL": "pkg:npm/undici",
          "product": "undici",
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            },
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  ],
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    }
  ],
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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-2026-84890 (GCVE-0-2026-84890)

FKIE_CVE-2026-84890

Tags

Sightings

Nomenclature