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TI-2026-04396 Aliases CVE-2026-5038GHSA-3p4h-7m6x-2hcm

multer vulnerable to Denial of Service via incomplete cleanup of aborted uploads

Priority LOW 39CWE-459Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
—
Confidentiality · integrity · availability
None · None · High
Fix status
Partial Red Hat: 4 fixed, 1 without a fix

Attack profile from CVSS 3.1 · NVD. Fix status from CNA, GitHub and Red Hat.

Summary

Impact: multer versions 2.0.0-alpha.1 through 2.1.1 and 3.0.0-alpha.1 are vulnerable to a Denial of Service when using diskStorage. Aborted or malformed multipart uploads leave orphaned partial files on disk because the Readable.pipe() call does not propagate the stream destroy signal to the underlying fs.WriteStream. An attacker can exhaust disk space by triggering many aborted uploads, with no application bug required. Patches: Users should upgrade to multer 2.2.0 (2.x line) or 3.0.0-alpha.2 (3.x prerelease). Both versions track in-flight write streams and clean them up on the abort path. Workarounds: None.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00367 30th percentileScored 2026-11-07
Fix Partial multer (multer): 2.2.0, 3.0.0-alpha.2multer (npm): 2.2.0, 3.0.0-alpha.2Red Hat: 5 advisoriesRed Hat: 4 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
expressjsmulter2.0.0-alpha.1 to before 2.2.0; 3.0.0-alpha.1 to before 3.0.0-alpha.22.2.0, 3.0.0-alpha.2Patch availableCNA
—multer (npm)2.0.0-alpha.1 to before 2.2.02.2.0Patch availableGHSA-3p4h-7m6x-2hcm
—multer (npm)3.0.0-alpha.1 to before 3.0.0-alpha.23.0.0-alpha.2Patch availableGHSA-3p4h-7m6x-2hcm
  • multer Vendorexpressjs Affected 2.0.0-alpha.1 to before 2.2.0; 3.0.0-alpha.1 to before 3.0.0-alpha.2 Fixed in 2.2.0, 3.0.0-alpha.2 Patch available CNA
  • multer (npm) Vendor— Affected 2.0.0-alpha.1 to before 2.2.0 Fixed in 2.2.0 Patch available GHSA-3p4h-7m6x-2hcm
  • multer (npm) Vendor— Affected 3.0.0-alpha.1 to before 3.0.0-alpha.2 Fixed in 3.0.0-alpha.2 Patch available GHSA-3p4h-7m6x-2hcm

CPE configurations NVD · 2

CPEVersionsRoleVendor
cpe:2.3:a:expressjs:multer:*:*:*:*:*:node.js:*:*2.0.0 to before 2.2.0Vulnerableexpressjs
cpe:2.3:a:expressjs:multer:3.0.0:alpha1:*:*:*:node.js:*:*3.0.0 alpha1Vulnerableexpressjs
  • cpe:2.3:a:expressjs:multer:*:*:*:*:*:node.js:*:* Versions 2.0.0 to before 2.2.0 Vulnerable ·expressjs
  • cpe:2.3:a:expressjs:multer:3.0.0:alpha1:*:*:*:node.js:*:* Versions 3.0.0 alpha1 Vulnerable ·expressjs

Remediation

  • Fix · CNA multer (multer) Fixed in 2.2.0, 3.0.0-alpha.2
  • Fix · GHSA-3p4h-7m6x-2hcm multer (npm) Fixed in 2.2.0 Advisory →
  • Fix · GHSA-3p4h-7m6x-2hcm multer (npm) Fixed in 3.0.0-alpha.2 Advisory →

Red Hat 5 advisories

  • RHSA-2026:73404 Released 2026-09-29 · Red Hat rating Important
    Ansible automation portal Red Hat Enterprise Linux Images
    • Red Hat Ansible Automation Platform 2.2 registry.redhat.io/ansible-automation-platform/bootc-automation-portal-rhel9
  • RHSA-2026:72712 Released 2026-09-28 · Red Hat rating Important
    Ansible plug-ins for Red Hat Developer Hub Product Release Update
    • Red Hat Ansible Automation Platform 2.1 registry.redhat.io/ansible-automation-platform/automation-portal
  • RHSA-2026:52768 Released 2026-08-10 · Red Hat rating Important
    Red Hat Developer Hub 1.9.8 release.
    • Red Hat Developer Hub 1.9 registry.redhat.io/rhdh/rhdh-hub-rhel9
Show 2 more Red Hat advisories
  • RHSA-2026:49642 Released 2026-08-03 · Red Hat rating Important
    Red Hat Developer Hub 1.10.3 release.
    • Red Hat Developer Hub 1.10 registry.redhat.io/rhdh/rhdh-hub-rhel9, registry.redhat.io/rhdh/rhdh-rhel9-operator
  • RHSA-2026:48126 Released 2026-07-29 · Red Hat rating Important
    Red Hat Developer Hub 1.10.3 Plugin Catalog GA plugins release.
    • Red Hat Developer Hub 1.10 registry.redhat.io/rhdh/red-hat-developer-hub-backstage-plugin-lightspeed, registry.redhat.io/rhdh/red-hat-developer-hub-backstage-plugin-lightspeed-backend, registry.redhat.io/rhdh/red-hat-developer-hub-backstage-plugin-orchestrator +4

Fixed in the same release

Records fixed by the same vendor advisory or release, as the CNA lists them.

  • Release ·

    multer 2.2.0, 3.0.0-alpha.2

    2 records Highest priority Priority LOW 2 LOW

    Other records, highest priority first

    • TI-2026-04434 multer vulnerable to Denial of Service via deeply nested field namesPriority LOW 39

Vendor assessments

Red Hat

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

ProductStatusPlan or fix
Logging Subsystem for Red Hat OpenShiftAffectedNo fix yet
Red Hat Ansible Automation Platform 2.1Fixed RHSA-2026:72712
Red Hat Ansible Automation Platform 2.2Fixed RHSA-2026:73404
Red Hat Developer Hub 1.10Fixed RHSA-2026:48126, RHSA-2026:49642
Red Hat Developer Hub 1.9Fixed RHSA-2026:52768
Not affected: 7 products
  • Red Hat Developer Hub 1.10
  • Red Hat Developer Hub 1.9
  • Red Hat Enterprise Linux 10
  • Red Hat Enterprise Linux 7
  • Red Hat Enterprise Linux 8
  • Red Hat Enterprise Linux 9
  • Red Hat Trusted Profile Analyzer

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-5038
  2. 2026-10-03 Alias added: GHSA-3p4h-7m6x-2hcm

References

  • TI-2026-03033 Multer vulnerable to Denial of Service via uncontrolled recursion CVSS 4.0HIGH 8.7
  • 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
See all 8 →

Sources