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📦
📦 npm
Not in CISA KEV
HIGH severity

CVE-2020-15779

HIGH

CVE-2020-15779 is a high-severity (CVSS 7.5) Path Traversal vulnerability in socket.io-file. 1 public exploit reference exists, so weaponization risk is real. O3 Security confirms whether CVE-2020-15779 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.

Path Traversal in socket.io-file

Published
Jul 7, 2020
Updated
May 4, 2026
Affected
1 pkg
Patched
None yet
Exploits
1 known
Exploitation data as of May 4, 2026 · OSV.dev, NVD, FIRST.org (EPSS)

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.

3other npm packages depend on this — each one inherits the vulnerability until it's patched upstream
socket.io-filenpm
531downloads / week

Description

All versions of socket.io-file are vulnerable to Path Traversal. The package fails to sanitize user input and uses it to generate the file upload paths. The socket.io-file::createFile message contains a name option that is passed directly to path.join(). It is possible to upload files to arbitrary folders on the server by sending relative paths on the name value, such as ../../test.js. The uploadDir and rename options can be used to define the file upload path.

Affected Packages

1 total
EcosystemPackageVulnerable rangeFix
📦npmsocket.io-fileall versionsNo fix
Exploits & PoCs
1

Research use only. For defensive security, authorized penetration testing, and academic research only. Never execute exploit code against systems without explicit written authorization.

Detection & mitigation playbook

Open-source dependency
  1. Detect

    Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for socket.io-file. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.

  2. Remediation status

    No patched version of socket.io-file has shipped for CVE-2020-15779 yet. Where your build allows, override or pin the dependency away from the vulnerable range, and apply any maintainer-recommended mitigation.

  3. Mitigate without a patch

    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 pinpoints whether CVE-2020-15779 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.

Tailored to CVE-2020-15779. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.

Frequently Asked Questions

All versions of `socket.io-file` are vulnerable to Path Traversal. The package fails to sanitize user input and uses it to generate the file upload paths. The `socket.io-file::createFile` message contains a `name` option that is passed directly to `path.join()`. It is possible to upload files to arbitrary folders on the server by sending relative paths on the `name` value, such as `../../test.js`. The `uploadDir` and `rename` options can be used to define the file upload path.
O3 Security · Impact-Aware SCA

Is CVE-2020-15779 in your dependencies?

O3 detects CVE-2020-15779 across npm dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.