Vulnerability-Lookup

GHSA-65X3-RW7Q-GX94

Vulnerability from github – Published: 2026-05-18 17:40 – Updated: 2026-05-18 17:40

Summary

multiparty vulnerable to ReDoS via filename parsing

Details

Impact

multiparty@4.2.3 and lower versions are vulnerable to denial of service via regular expression backtracking in the Content-Disposition filename parameter parser. A multipart upload with a long header value containing !filename="1 repeated can cause regex matching to take seconds, blocking the event loop. Any service accepting multipart uploads via multiparty is affected.

Patches

Users should upgrade to multiparty@4.3.0 or higher.

Workarounds

None. Limiting upload sizes at the proxy/gateway layer reduces but does not eliminate the attack surface, since a small ~8 KB header is sufficient to trigger the vulnerable backtracking.

Resources

OWASP: Regular expression Denial of Service (ReDoS)

Severity ?

7.5 (High)


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

Show details on source website

JSON

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{
  "affected": [
    {
      "database_specific": {
        "last_known_affected_version_range": "\u003c= 4.2.3"
      },
      "package": {
        "ecosystem": "npm",
        "name": "multiparty"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "4.3.0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-8159"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-1333"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-05-18T17:40:10Z",
    "nvd_published_at": "2026-05-12T10:16:48Z",
    "severity": "HIGH"
  },
  "details": "### Impact\n\nmultiparty@4.2.3 and lower versions are vulnerable to denial of service via regular expression backtracking in the `Content-Disposition` filename parameter parser. A multipart upload with a long header value containing `!filename=\"1` repeated can cause regex matching to take seconds, blocking the event loop. Any service accepting multipart uploads via multiparty is affected.\n\n### Patches\n\nUsers should upgrade to multiparty@4.3.0 or higher.\n\n### Workarounds\n\nNone. Limiting upload sizes at the proxy/gateway layer reduces but does not eliminate the attack surface, since a small ~8 KB header is sufficient to trigger the vulnerable backtracking.\n\n### Resources\n\n- [OWASP: Regular expression Denial of Service (ReDoS)](https://owasp.org/www-community/attacks/Regular_expression_Denial_of_Service_-_ReDoS)",
  "id": "GHSA-65x3-rw7q-gx94",
  "modified": "2026-05-18T17:40:10Z",
  "published": "2026-05-18T17:40:10Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/pillarjs/multiparty/security/advisories/GHSA-65x3-rw7q-gx94"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-8159"
    },
    {
      "type": "WEB",
      "url": "https://cna.openjsf.org/security-advisories.html"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/pillarjs/multiparty"
    },
    {
      "type": "WEB",
      "url": "https://github.com/pillarjs/multiparty/releases/tag/v4.3.0"
    },
    {
      "type": "WEB",
      "url": "https://owasp.org/www-community/attacks/Regular_expression_Denial_of_Service_-_ReDoS"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    }
  ],
  "summary": "multiparty vulnerable to ReDoS via filename parsing"
}

CVE-2026-8159 (GCVE-0-2026-8159)

Vulnerability from cvelistv5 – Published: 2026-05-12 08:35 – Updated: 2026-05-12 12:33

Title

multiparty vulnerable to ReDoS via filename parsing

Summary

multiparty@4.2.3 and lower versions are vulnerable to denial of service via regular expression backtracking in the Content-Disposition filename parameter parser. A crafted multipart upload with a long header value can cause regex matching to take seconds, blocking the event loop. Impact: any service accepting multipart uploads via multiparty is affected. Workarounds: limiting upload sizes at the proxy or gateway layer reduces but does not eliminate the attack surface, since a small header of around 8 KB is sufficient to trigger the vulnerable backtracking. Upgrade to multiparty@4.3.0 or higher.

Severity ?

7.5 (High)


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

CWE

CWE-1333 - Inefficient Regular Expression Complexity

Assigner

openjs

References

3 references

URL	Tags
https://github.com/pillarjs/multiparty/security/a…
https://owasp.org/www-community/attacks/Regular_e…
https://cna.openjsf.org/security-advisories.html

Impacted products

1 product

Vendor	Product	Version
multiparty	multiparty	Affected: 0 , ≤ 4.2.3 (semver) Unaffected: 4.3.0 (semver)

Credits

aszx87410 Blake Embrey Ulises Gascón

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
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                "id": "CVE-2026-8159",
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                  },
                  {
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                "role": "CISA Coordinator",
                "timestamp": "2026-05-12T12:33:48.310208Z",
                "version": "2.0.3"
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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.

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