CVE-2021-43521

Name: CVE-2021-43521
Creator: NVD / NIST
Published: 2022-04-08T16:15:08.2+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

HIGHCVSS 7.5/10EPSS 1.26%

Last modified Jun 17, 2026

CVE-2021-43521 is a high-severity vulnerability rated 7.5/10 on the CVSS scale. A Buffer Overflow vulnerability exists in zlog 1.2.15 via zlog_conf_build_with_file in src/zlog/src/conf.c.. EPSS estimates a 1.26% chance of exploitation in the next 30 days.

Description

A Buffer Overflow vulnerability exists in zlog 1.2.15 via zlog_conf_build_with_file in src/zlog/src/conf.c.

Metrics

CVSS 3.1

7.5/10

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

EPSS Probability

1.26%

65.9th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-787

Affected Software

Vendor	Product	Versions
Zlog Project	Zlog	1.2.15

References

https://github.com/HardySimpson/zlogProduct, Third Party Advisory
https://github.com/HardySimpson/zlog/issues/206Exploit, Issue Tracking, Third Party Advisory
https://github.com/HardySimpson/zlogProduct, Third Party Advisory
https://github.com/HardySimpson/zlog/issues/206Exploit, Issue Tracking, Third Party Advisory

Timeline

Published: Apr 8, 2022
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2021-43521?

A Buffer Overflow vulnerability exists in zlog 1.2.15 via zlog_conf_build_with_file in src/zlog/src/conf.c.

How severe is CVE-2021-43521?

CVE-2021-43521 has a CVSS score of 7.5/10 (HIGH severity). The EPSS model estimates a 1.26% probability of exploitation in the next 30 days.

How do I fix CVE-2021-43521?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2021-43521?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST