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TI-2026-03033 Aliases CVE-2026-3520GHSA-5528-5vmv-3xc2

Multer vulnerable to Denial of Service via uncontrolled recursion

Priority MEDIUM 45CWE-674Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Attack requirements
None
Impact type
Denial of service
Confidentiality · integrity · availability
None · None · High
Fix status
Partial Red Hat: 2 fixed, 1 without a fix

Attack profile from CVSS 4.0 · CNA. Fix status from CNA, GitHub and Red Hat. Impact type from CWE-674.

Summary

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.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00818 57th percentileScored 2026-11-07
Fix Partial multer (expressjs): 2.1.1multer (npm): 2.1.1Red Hat: 2 advisoriesRed Hat: 2 fixed, 1 without a fix

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
Yes
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
expressjsmulterbefore 2.1.12.1.1Patch availableCNA
—multer (npm)before 2.1.12.1.1Patch availableGHSA-5528-5vmv-3xc2
  • multer Vendorexpressjs Affected before 2.1.1 Fixed in 2.1.1 Patch available CNA
  • multer (npm) Vendor— Affected before 2.1.1 Fixed in 2.1.1 Patch available GHSA-5528-5vmv-3xc2

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:expressjs:multer:*:*:*:*:*:node.js:*:*before 2.1.1Vulnerableexpressjs
  • cpe:2.3:a:expressjs:multer:*:*:*:*:*:node.js:*:* Versions before 2.1.1 Vulnerable ·expressjs

Remediation

  • Fix · CNA multer (expressjs) Fixed in 2.1.1
  • Fix · GHSA-5528-5vmv-3xc2 multer (npm) Fixed in 2.1.1 Advisory →

Red Hat 2 advisories

  • RHSA-2026:6802 Released 2026-04-07 · Red Hat rating Important
    Red Hat Developer Hub 1.9.3 release.
    • Red Hat Developer Hub 1.9 registry.redhat.io/rhdh/rhdh-hub-rhel9, registry.redhat.io/rhdh/rhdh-rhel9-operator
  • RHSA-2026:6174 Released 2026-03-30 · Red Hat rating Important
    Red Hat Developer Hub 1.8.5 release.
    • Red Hat Developer Hub 1.8 registry.redhat.io/rhdh/rhdh-hub-rhel9, registry.redhat.io/rhdh/rhdh-rhel9-operator

Vendor assessments

Red Hat

Red Hat rating: Important. Red Hat's page for this CVE →

ProductStatusPlan or fix
Self-service automation portal 2AffectedNo fix yet
Red Hat Developer Hub 1.8Fixed RHSA-2026:6174
Red Hat Developer Hub 1.9Fixed RHSA-2026:6802
Not affected: 2 products
  • Red Hat Developer Hub 1.8
  • Red Hat Developer Hub 1.9

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-3520
  2. 2026-10-03 Alias added: GHSA-5528-5vmv-3xc2

References

Patch 1

Advisory 4

Other 1

  • TI-2026-02853 Multer vulnerable to Denial of Service via incomplete cleanup CVSS 4.0HIGH 8.7
  • TI-2026-01995 Multer vulnerable to Denial of Service via resource exhaustion CVSS 4.0HIGH 8.7
  • TI-2026-56780 multer vulnerable to Denial of Service via oversized array index in field names CVSS 3.1HIGH 7.5
  • TI-2026-53831 multer vulnerable to Denial of Service via crafted multipart field names CVSS 3.1HIGH 7.5
  • TI-2026-53816 multer vulnerable to Denial of Service via file descriptor leak on aborted uploads CVSS 3.1HIGH 7.5
  • TI-2026-04434 multer vulnerable to Denial of Service via deeply nested field names CVSS 3.1HIGH 7.5
See all 8 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences