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

Vulnerability from cvelistv5 – Published: 2026-05-12 08:35 – Updated: 2026-05-12 12:33
VLAI?
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
References
Impacted products
Vendor Product Version
multiparty multiparty Affected: 0 , ≤ 4.2.3 (semver)
Unaffected: 4.3.0 (semver)
Create a notification for this product.
Credits
aszx87410 Blake Embrey Ulises Gascón
Show details on NVD website
To clipboard 

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Sightings

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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.
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