highCVSS 7.5Vulnerability

CVE-2026-8159

### Impact [email protected] 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 [email protected] 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)](https://owasp.org/www-community/attacks/Regular_expression_Denial_of_Service_-_ReDoS)

Properties

summary
multiparty vulnerable to ReDoS via filename parsing
severity
high
epss_score
0.00335
cvss_score
7.5
ghsa_published
2026-05-18T17:40:10Z
source_url
https://github.com/advisories/GHSA-65x3-rw7q-gx94
ghsa_updated
2026-05-18T17:40:10Z
ghsa_id
GHSA-65x3-rw7q-gx94
cve_id
CVE-2026-8159
cvss_vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
is_ghsa_only
false
epss_percentile
0.26575

Related Entities (5)

ENRICHED_BY (1)

[Source]FIRST EPSS

AFFECTS (1)

[Software]npm/multiparty

HAS_WEAKNESS (1)

[Weakness]Inefficient Regular Expression Complexity

REPORTED_BY (1)

[Source]GitHub Advisory Database

VULNERABLE_TO (1)

[Software]npm/multiparty

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CVE-2026-8159 (CVSS 7.5) — Ninja Signal Threat Intelligence | Ninja Signal