All vulnerabilities
CVE-2026-88932GHSA-3pph-fpjx-jg34

multer vulnerable to Denial of Service via orphaned disk writes on aborted uploads

multer multernpmLibraries & packages
Open in ThreatlineRecord JSON
CVSS
5.3Medium
ExploitationNo known exploitationNot in CISA KEV, which does not prove it is unexploitedCISA KEV
Exploit odds (EPSS)0.53%Chance of exploitation activity in the next 30 days, higher than 44% of CVEs. Scored 23 Oct 2026FIRST EPSS
Fixed in2.4.0Fixed versionGitHub
Published14 Sep 2026Updated 28 Sep 2026CVE List

What fixes it

A fixed version on one release line is not the upgrade target for every line. Check your exact version and any vendor backports.

Description

Impact

Multer's diskStorage can leave complete, orphaned files on disk when a multipart upload is aborted in the brief window before the storage engine assigns the file path. This is an incomplete fix of CVE-2026-5038: the earlier cleanup removes only in-flight uploads that already have a path, so an upload aborted inside that window is written to disk with nothing left to remove it, and the application is not given a handle to clean it up. An unauthenticated attacker sending aborted requests to any route backed by disk storage can accumulate orphaned files until the upload directory or the shared system temporary directory is exhausted. An asynchronous destination or filename widens the window.

Patches

Users should upgrade to 2.4.0 or higher.

Workarounds

None.

Text from GitHub Advisory Database

Affected versions 4

  • multer, npm>= 2.2.0, < 2.4.0GitHub
  • multeraffected: 2.2.0 before 2.4.0CVE List
  • multerunaffected: 2.4.0CVE List
  • multer, npmfrom 2.2.0, fixed in 2.4.0OSV

References 6