CVE-2021-1405

Name: CVE-2021-1405
Creator: NVD / NIST
Published: 2021-04-08T05:15:13.347+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

HIGHCVSS 7.5/10EPSS 3.16%

Last modified Jun 17, 2026

CVE-2021-1405 is a high-severity vulnerability rated 7.5/10 on the CVSS scale. A vulnerability in the email parsing module in Clam AntiVirus (ClamAV) Software version 0.103.1 and all prior versions could allow an unauthenticated, remote attacker to cause a denial of service condition on an affected device. The vulnerability is due to improper variable initialization that may result in an NULL pointer read. EPSS estimates a 3.16% chance of exploitation in the next 30 days.

Description

A vulnerability in the email parsing module in Clam AntiVirus (ClamAV) Software version 0.103.1 and all prior versions could allow an unauthenticated, remote attacker to cause a denial of service condition on an affected device. The vulnerability is due to improper variable initialization that may result in an NULL pointer read. An attacker could exploit this vulnerability by sending a crafted email to an affected device. An exploit could allow the attacker to cause the ClamAV scanning process crash, resulting in a denial of service condition.

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

3.16%

86.3th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

Affected Software

Vendor	Product	Versions
Clamav	Clamav	<= 0.103.1
Debian	Debian Linux	9.0

References

https://blog.clamav.net/2021/04/clamav-01032-security-patch-release.htmlRelease Notes, Vendor Advisory
https://lists.debian.org/debian-lts-announce/2021/04/msg00012.htmlMailing List, Third Party Advisory
https://security.gentoo.org/glsa/202104-07Third Party Advisory
https://blog.clamav.net/2021/04/clamav-01032-security-patch-release.htmlRelease Notes, Vendor Advisory
https://lists.debian.org/debian-lts-announce/2021/04/msg00012.htmlMailing List, Third Party Advisory
https://security.gentoo.org/glsa/202104-07Third Party Advisory

Timeline

Published: Apr 8, 2021
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2021-1405?

How severe is CVE-2021-1405?

CVE-2021-1405 has a CVSS score of 7.5/10 (HIGH severity). The EPSS model estimates a 3.16% probability of exploitation in the next 30 days.

How do I fix CVE-2021-1405?

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-2021-1405?

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

Scan your code now

Source: NVD / NIST