CVE-2026-8159
multiparty vulnerable to ReDoS via filename parsing
Description
[email protected] 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 [email protected] or higher.
INFO
Published Date :
May 12, 2026, 10:16 a.m.
Last Modified :
May 13, 2026, 2:44 p.m.
Remotely Exploit :
Yes !
Source :
ce714d77-add3-4f53-aff5-83d477b104bb
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 3.1 | HIGH | ce714d77-add3-4f53-aff5-83d477b104bb | ||||
| CVSS 3.1 | HIGH | MITRE-CVE |
Solution
- Upgrade multiparty to version 4.3.0 or higher.
- Limit upload sizes at the proxy or gateway.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-8159.
| URL | Resource |
|---|---|
| https://cna.openjsf.org/security-advisories.html | Third Party Advisory |
| https://github.com/pillarjs/multiparty/security/advisories/GHSA-65x3-rw7q-gx94 | Mitigation Vendor Advisory |
| https://owasp.org/www-community/attacks/Regular_expression_Denial_of_Service_-_ReDoS | Not Applicable |
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-8159 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-8159
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-8159 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-8159 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
Initial Analysis by [email protected]
May. 13, 2026
Action Type Old Value New Value Added CPE Configuration OR *cpe:2.3:a:pillarjs:multiparty:*:*:*:*:*:node.js:*:* versions up to (excluding) 4.3.0 Added Reference Type openjs: https://cna.openjsf.org/security-advisories.html Types: Third Party Advisory Added Reference Type openjs: https://github.com/pillarjs/multiparty/security/advisories/GHSA-65x3-rw7q-gx94 Types: Mitigation, Vendor Advisory Added Reference Type openjs: https://owasp.org/www-community/attacks/Regular_expression_Denial_of_Service_-_ReDoS Types: Not Applicable -
New CVE Received by ce714d77-add3-4f53-aff5-83d477b104bb
May. 12, 2026
Action Type Old Value New Value Added Description [email protected] 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 [email protected] or higher. Added CVSS V3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H Added CWE CWE-1333 Added Reference https://cna.openjsf.org/security-advisories.html Added Reference https://github.com/pillarjs/multiparty/security/advisories/GHSA-65x3-rw7q-gx94 Added Reference https://owasp.org/www-community/attacks/Regular_expression_Denial_of_Service_-_ReDoS