Your RSA-2048 keys break in 2030. Find every one of them before attackers do.
📦
📦 npm
Not in CISA KEV
HIGH severity

GHSA-4pg4-qvpc-4q3h — multer

HIGHFix: expressjs/multer@2c8505f

GHSA-4pg4-qvpc-4q3h is a high-severity (CVSS 7.5) CWE-248 vulnerability in multer. A fix is available for multer — see the affected versions and patch details below.

Multer vulnerable to Denial of Service from maliciously crafted requests

Also known asCVE-2025-47944
Published
May 19, 2025
Updated
Sep 10, 2026
Affected
1 pkg
Patched
1 / 1
Exploits
None indexed
Exploitation data as of Sep 24, 2026 · OSV.dev, NVD, FIRST.org (EPSS)

Exploitation Status

No confirmed exploitation observed yet

  • CISA assesses this as automatable — exploitation doesn’t require manual, per-target effort, which raises the odds of mass scanning and opportunistic attacks.
  • CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.

Exploitation and automatability from CISA’s SSVC triage for GHSA-4pg4-qvpc-4q3h.

EPSS Exploitation Probability

via FIRST.org ↗
0.8%probability of exploitation in next 30 days
Lower Risk0.00%
Lower risk than most CVEs55th percentile — riskier than 55% of all scored CVEsHighest risk

EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.

How urgent is this, really

GHSA-4pg4-qvpc-4q3h plotted by exploitation likelihood (EPSS) against impact (CVSS). The shaded corner — EPSS 50%+ and CVSS 7.0+ — is where this CVE doesn't sit, though severity or exploitability alone can still warrant action.

Where this sits among everything scored

Of 379,145 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Real counts from FIRST.org, not a sample — log-scaled since the landscape is heavily right-skewed.

Real-World Exposure

1 pkg affected

How broadly this vulnerability is actually deployed: weekly install volume shows current usage, and reverse-dependency count shows how many other packages break if it stays unpatched.

7Kother npm packages depend on this — each one inherits the vulnerability until it's patched upstream
multernpm
15.3Mdownloads / week

Description

Impact

A vulnerability in Multer versions >=1.4.4-lts.1 allows an attacker to trigger a Denial of Service (DoS) by sending a malformed multi-part upload request. This request causes an unhandled exception, leading to a crash of the process.

Patches

Users should upgrade to 2.0.0

Workarounds

None

References

Affected Packages

1 total 1 fixed
EcosystemPackageVulnerable rangeFix
📦npmmulter≥ 1.4.4-lts.1&&< 2.0.02.0.0npm install multer@2.0.0

Detection & mitigation playbook

Open-source dependency
  1. Detect

    Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for multer, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.

  2. Fix

    Update multer to 2.0.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-4pg4-qvpc-4q3h is resolved across your whole dependency graph.

  3. Workarounds

    If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.

  4. How O3 protects you

    O3 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like GHSA-4pg4-qvpc-4q3h can be triaged on real exposure rather than presence alone.

Tailored to GHSA-4pg4-qvpc-4q3h. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.

Frequently Asked Questions

### Impact A vulnerability in Multer versions >=1.4.4-lts.1 allows an attacker to trigger a Denial of Service (DoS) by sending a malformed multi-part upload request. This request causes an unhandled exception, leading to a crash of the process. ### Patches Users should upgrade to `2.0.0` ### Workarounds None ### References - https://github.com/expressjs/multer/issues/1176 - https://github.com/expressjs/multer/commit/2c8505f207d923dd8de13a9f93a4563e59933665
O3 Security · Impact-Aware SCA

Is GHSA-4pg4-qvpc-4q3h in your dependencies?

O3 Security finds GHSA-4pg4-qvpc-4q3h across npm dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.

GHSA-4pg4-qvpc-4q3h: multer DoS (High 7.5) | O3 Security