CVE-2025-47935 json
Multer vulnerable to Denial of Service via memory leaks from unclosed streams
published last yr. modified last mo. also EUVD-2025-15797 , GHSA-44fp-w29j-9vj5
- cvss
- 7.5
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.8%
- EPSS 0.8% chance of exploitation in 30 days, percentile 56%
- public exploits
- 0
- none known
Summary
Multer is a node.js middleware for handling `multipart/form-data`. Versions prior to 2.0.0 are vulnerable to a resource exhaustion and memory leak issue due to improper stream handling. When the HTTP request stream emits an error, the internal `busboy` stream is not closed, violating Node.js stream safety guidance. This leads to unclosed streams accumulating over time, consuming memory and file descriptors. Under sustained or repeated failure conditions, this can result in denial of service, requiring manual server restarts to recover. All users of Multer handling file uploads are potentially impacted. Users should upgrade to 2.0.0 to receive a patch. No known workarounds are available.
Patch / fix
- npm multer 2.0.0
- expressjs multer 2.0.0
- github.com/expressjs/multer@2c8505f commit
- github.com/expressjs/multer#1120 pull request
Is CVE-2025-47935 in your dependencies? Fencer shows which of your repositories are affected as soon as an advisory lands, and opens the fix as a pull request.
Check with FencerCISA SSVC
- Exploitation
- none
- Automatable
- yes
- Technical impact
- partial
- Assessed
- last yr.
Exploit prediction
0.80% chance of exploitation in the next 30 days, higher than 56% of all scored CVEs (FIRST EPSS, 2026-11-09).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
| GitHub | 3.1 | 7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
Affected packages
| ecosystem | package | affected | fixed in |
|---|---|---|---|
| npm | multer | <2.0.0 |
2.0.0 |
Affected products
- expressjs multer
Classification
- Weakness
-
- CWE-401 Missing Release of Memory after Effective Lifetime
References
Sources
- CVE List CVE-2025-47935
- GitHub Advisory GHSA-44fp-w29j-9vj5
- NVD CVE-2025-47935
Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.
CPEs and fixed versions use Anchore's correction of NVD's data: Added CPE configurations because not yet analyzed by NVD.