Vulnerability-Lookup

GHSA-8436-99HF-9MMV

Vulnerability from github – Published: 2026-09-29 18:16 – Updated: 2026-09-29 18:16

Summary

undici vulnerable to caching and replay of unsafe HTTP method responses

Details

Impact

undici's interceptors.cache() documents that it caches only safe HTTP methods. However, its internal skip-list is built by subtracting the configured methods from the safe-methods set, so an unsafe method (POST, PUT, PATCH, DELETE) never lands in the skip-list and is looked up against the cache store. Combined with the storage gate (canCacheResponse) having no method check, a heuristically-cacheable response (for example a 404) with an explicit Cache-Control: max-age=... to an unsafe method is stored and replayed on a subsequent identical request. The application's state-changing request never reaches the origin, and undici serves a fabricated response from the cache instead. This occurs with the default configuration (methods: ['GET']), which the public API does not allow widening to unsafe methods, so no application misuse is required; an untrusted origin can trigger it purely through its own response headers.

Patches

Upgrade to 7.29.1 or 8.10.2. The cache interceptor no longer reads from or writes to the cache for unsafe HTTP methods, while still invalidating existing cache entries on successful unsafe requests.

Workarounds

None.

Severity

3.7 (Low)


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

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{
  "affected": [
    {
      "package": {
        "ecosystem": "npm",
        "name": "undici"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "7.0.0"
            },
            {
              "fixed": "7.29.1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "npm",
        "name": "undici"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "8.0.0"
            },
            {
              "fixed": "8.10.2"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-85008"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-345"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-09-29T18:16:28Z",
    "nvd_published_at": "2026-09-04T17:17:02Z",
    "severity": "LOW"
  },
  "details": "### Impact\n\nundici\u0027s `interceptors.cache()` documents that it caches only safe HTTP methods. However, its internal skip-list is built by subtracting the configured methods from the safe-methods set, so an unsafe method (`POST`, `PUT`, `PATCH`, `DELETE`) never lands in the skip-list and is looked up against the cache store. Combined with the storage gate (`canCacheResponse`) having no method check, a heuristically-cacheable response (for example a `404`) with an explicit `Cache-Control: max-age=...` to an unsafe method is stored and replayed on a subsequent identical request. The application\u0027s state-changing request never reaches the origin, and undici serves a fabricated response from the cache instead. This occurs with the default configuration (`methods: [\u0027GET\u0027]`), which the public API does not allow widening to unsafe methods, so no application misuse is required; an untrusted origin can trigger it purely through its own response headers.\n\n### Patches\n\nUpgrade to `7.29.1` or `8.10.2`. The cache interceptor no longer reads from or writes to the cache for unsafe HTTP methods, while still invalidating existing cache entries on successful unsafe requests.\n\n### Workarounds\n\nNone.",
  "id": "GHSA-8436-99hf-9mmv",
  "modified": "2026-09-29T18:16:28Z",
  "published": "2026-09-29T18:16:28Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/nodejs/undici/security/advisories/GHSA-8436-99hf-9mmv"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-85008"
    },
    {
      "type": "WEB",
      "url": "https://github.com/nodejs/undici/commit/2be07bf97b3022e0324142d31f99f6e019d815e3"
    },
    {
      "type": "WEB",
      "url": "https://github.com/nodejs/undici/commit/b61d9432bac7caac51273ad209862e4c0bf935ae"
    },
    {
      "type": "WEB",
      "url": "https://cna.openjsf.org/security-advisories.html"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/nodejs/undici"
    },
    {
      "type": "WEB",
      "url": "https://github.com/nodejs/undici/releases/tag/v7.29.1"
    },
    {
      "type": "WEB",
      "url": "https://github.com/nodejs/undici/releases/tag/v8.10.2"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N",
      "type": "CVSS_V3"
    }
  ],
  "summary": "undici vulnerable to caching and replay of unsafe HTTP method responses"
}

CVE-2026-85008 (GCVE-0-2026-85008)

Vulnerability from cvelistv5 – Published: 2026-09-04 16:42 – Updated: 2026-09-04 19:28

Title

undici vulnerable to caching and replay of unsafe HTTP method responses

Summary

undici's cache interceptor documents that only safe HTTP methods are cached, but its logic to skip caching is built by subtracting the configured methods from the set of safe methods, so an unsafe method such as POST, PUT, or DELETE is never placed in the skip list and instead falls through to the full cache-read path. The response-storage gate also lacked a method check, so a response to an unsafe request that is heuristically cacheable or carries an explicit Cache-Control directive is stored and later replayed from cache. Because response headers from a remote origin are untrusted, an origin can answer once with a cacheable status and then have the client's own subsequent state-changing requests to that path served from the stale cache entry without ever reaching the origin, an integrity failure that occurs under the interceptor's default configuration. This affects undici versions from 7.0.0 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

3.7 (Low)


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

SSVC

Exploitation: none Automatable: no Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-09-04 19:28 UTC

CWE

CWE-345 - Insufficient Verification of Data Authenticity

Assigner

openjs redhat root Scorecard

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: 7.0.0 , < 7.29.1 (semver) Unaffected: 7.29.1 (semver) Affected: 8.0.0 , < 8.10.2 (semver) Unaffected: 8.10.2 (semver)

Credits

MegaManSec mcollina UlisesGascon

Show details on NVD website

JSON

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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.

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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