Vulnerability-Lookup

UBUNTU-CVE-2026-84890 (CVE-2026-84890)

Vulnerability from osv_ubuntu – Published: 2026-09-04 18:18 – Updated: 2026-09-16 11:43 – Source website

Details

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

N/A (UNKNOWN)


                    
                      medium

References

URL

Type

	https://ubuntu.com/security/CVE-2026-84890	REPORT
	https://www.cve.org/CVERecord?id=CVE-2026-84890	REPORT
	https://github.com/nodejs/undici/security/advisor…	REPORT

JSON

To clipboard

{
  "affected": [
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "node-llhttp",
            "binary_version": "9.1.3~5.26.3+dfsg1+~cs23.10.12-2"
          },
          {
            "binary_name": "node-undici",
            "binary_version": "5.26.3+dfsg1+~cs23.10.12-2"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:24.04:LTS",
        "name": "node-undici",
        "purl": "pkg:deb/ubuntu/node-undici@5.26.3+dfsg1+~cs23.10.12-2?arch=source\u0026distro=noble"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "5.22.1+dfsg1+~cs20.10.10.2-1ubuntu1",
        "5.26.3+dfsg1+~cs23.10.12-2"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "node-undici",
            "binary_version": "7.18.2+dfsg+~cs3.2.0-1build1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:26.04:LTS",
        "name": "node-undici",
        "purl": "pkg:deb/ubuntu/node-undici@7.18.2+dfsg+~cs3.2.0-1build1?arch=source\u0026distro=resolute"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "7.3.0+dfsg1+~cs24.12.11-2",
        "7.16.0+dfsg+~cs3.2.0-2",
        "7.18.2+dfsg+~cs3.2.0-1",
        "7.18.2+dfsg+~cs3.2.0-1build1"
      ]
    }
  ],
  "aliases": [],
  "details": "undici\u0027s 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.",
  "id": "UBUNTU-CVE-2026-84890",
  "modified": "2026-09-16T11:43:10Z",
  "published": "2026-09-04T18:18:00Z",
  "references": [
    {
      "type": "REPORT",
      "url": "https://ubuntu.com/security/CVE-2026-84890"
    },
    {
      "type": "REPORT",
      "url": "https://www.cve.org/CVERecord?id=CVE-2026-84890"
    },
    {
      "type": "REPORT",
      "url": "https://github.com/nodejs/undici/security/advisories/GHSA-3xpg-4rpp-hhhm"
    }
  ],
  "related": [],
  "schema_version": "1.7.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    },
    {
      "score": "medium",
      "type": "Ubuntu"
    }
  ],
  "upstream": [
    "CVE-2026-84890"
  ]
}

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

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
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)

Credits

mcollina UlisesGascon

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "adp": [
      {
        "metrics": [
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            "other": {
              "content": {
                "id": "CVE-2026-84890",
                "options": [
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                    "Exploitation": "none"
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                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-09-04T18:32:49.819558Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
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        "providerMetadata": {
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          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
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          "packageURL": "pkg:npm/undici",
          "product": "undici",
          "vendor": "undici",
          "versions": [
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              "status": "affected",
              "version": "7.15.0",
              "versionType": "semver"
            },
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              "versionType": "semver"
            },
            {
              "lessThan": "8.10.2",
              "status": "affected",
              "version": "8.0.0",
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            {
              "status": "unaffected",
              "version": "8.10.2",
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      "credits": [
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          "lang": "en",
          "type": "analyst",
          "value": "mcollina"
        },
        {
          "lang": "en",
          "type": "remediation reviewer",
          "value": "UlisesGascon"
        }
      ],
      "descriptions": [
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          "supportingMedia": [
            {
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        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "baseScore": 5.9,
            "baseSeverity": "MEDIUM",
            "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H",
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        "orgId": "ce714d77-add3-4f53-aff5-83d477b104bb",
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      "references": [
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          "url": "https://github.com/nodejs/undici/security/advisories/GHSA-3xpg-4rpp-hhhm"
        },
        {
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        }
      ],
      "title": "undici vulnerable to Denial of Service via unbounded decompression of compressed responses",
      "x_generator": {
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    }
  },
  "cveMetadata": {
    "assignerOrgId": "ce714d77-add3-4f53-aff5-83d477b104bb",
    "assignerShortName": "openjs",
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    "datePublished": "2026-09-04T17:04:28.261Z",
    "dateReserved": "2026-09-02T14:36:25.597Z",
    "dateUpdated": "2026-09-04T18:33:28.246Z",
    "state": "PUBLISHED"
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  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

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.

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.
Browse all ATT&CK techniques and the vulnerabilities related to each.

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UBUNTU-CVE-2026-84890 (CVE-2026-84890)

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

Tags

Sightings

Nomenclature

Related by attack behaviour