Is there a public exploit for CVE-2026-3520?

No public exploit for CVE-2026-3520 was found in Exploit-DB, Metasploit, Nuclei templates or public proof-of-concept repositories. That is an absence of evidence rather than proof that none exists.

How severe is CVE-2026-3520?

CVE-2026-3520 scores CVSS 8.7 (v4.0), rated high. EPSS puts the chance of exploitation in the next 30 days at 0.82%.

What does CVE-2026-3520 affect?

CVE-2026-3520 affects expressjs multer.

8.7 High

Multer is a node.js middleware for handling multipart/form-data.

CVE-2026-3520

Impact A vulnerability in Multer versions < 2.1.1 allows an attacker to trigger a Denial of Service (DoS) by sending malformed requests, potentially causing stack overflow. Patches Users should upgrade to 2.1.1 Workarounds None Resources https://github.com/expressjs/multer/security/advisories/GHSA-5528-5vmv-3xc2 https://www.cve.org/CVERecord?id=CVE-2026-3520 https://github.com/expressjs/multer/commit/7e66481f8b2e6c54b982b34c152479e096ce2752 https://cna.openjsf.org/security-advisories.html

Assessment

CVSS: 8.7 (v4.0)
Severity: High
EPSS: 0.82% chance of exploitation in the next 30 days
Known exploited: Not listed in CISA KEV
Exploit availability: Nothing found in Exploit-DB, Metasploit, Nuclei or public PoC repositories
Published: 4 March 2026
Last updated: 15 July 2026
Affected: expressjs · multer · multer
Weakness: CWE-674, CWE-770
Assigner: ce714d77-add3-4f53-aff5-83d477b104bb

CVSS vectorCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N

At the source

References

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