8.7High
CVE-2026-3520Multer vulnerable to Denial of Service via uncontrolled recursion
Description
Multer is a node.js middleware for handling `multipart/form-data`. A vulnerability in Multer prior to version 2.1.1 allows an attacker to trigger a Denial of Service (DoS) by sending malformed requests, potentially causing stack overflow. Users should upgrade to version 2.1.1 to receive a patch. No known workarounds are available.
Data: CVE.org, NVD, CISA KEV, FIRST EPSS, Ubuntu. Published as the sources state it, in English.
Affected products and versions
| Vendor | Product | Versions | |
|---|---|---|---|
| expressjs | multer | < 2.1.1 | |
| Red Hat | Red Hat Developer Hub 1.8 | all versions | |
| Red Hat | Red Hat Developer Hub 1.9 | all versions | |
| Red Hat | Self-service automation portal 2 | all versions | |
| rhdh | 1.8 | — | |
| rhdh | 1.9 | — |
References and patches
- https://github.com/expressjs/multer/security/advisories/GHSA-5528-5vmv-3xc2 Vendor Advisory
- https://www.cve.org/CVERecord?id=CVE-2026-3520 Third Party Advisory
- https://github.com/expressjs/multer/commit/7e66481f8b2e6c54b982b34c152479e096ce2752 Patch
- https://cna.openjsf.org/security-advisories.html Third Party Advisory
- https://access.redhat.com/errata/RHSA-2026:6174
- https://access.redhat.com/errata/RHSA-2026:6802
- https://access.redhat.com/security/cve/CVE-2026-3520
- https://bugzilla.redhat.com/show_bug.cgi?id=2444584
- https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-3520.json
CPE matches (NVD) (1)
cpe:2.3:a:expressjs:multer:*:*:*:*:*:node.js:*:*< 2.1.1