CVE-2021-3402

Name: CVE-2021-3402
Creator: NVD / NIST
Published: 2021-05-14T21:15:07.537+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

CRITICALCVSS 9.1/10EPSS 2.22%

Last modified Jun 17, 2026

CVE-2021-3402 is a critical-severity vulnerability rated 9.1/10 on the CVSS scale. An integer overflow and several buffer overflow reads in libyara/modules/macho/macho.c in YARA v4.0.3 and earlier could allow an attacker to either cause denial of service or information disclosure via a malicious Mach-O file. Affects all versions before libyara 4.0.4. EPSS estimates a 2.22% chance of exploitation in the next 30 days.

Description

An integer overflow and several buffer overflow reads in libyara/modules/macho/macho.c in YARA v4.0.3 and earlier could allow an attacker to either cause denial of service or information disclosure via a malicious Mach-O file. Affects all versions before libyara 4.0.4

Metrics

CVSS 3.1

9.1/10

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

EPSS Probability

2.22%

80.4th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-190

Affected Software

Vendor	Product	Versions
Virustotal	Yara	< 4.0.4
Fedoraproject	Fedora	33
Fedoraproject	Fedora	34

References

https://bugzilla.redhat.com/show_bug.cgi?id=1930175Issue Tracking, Third Party Advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/FKNXSH5ERG6NELTXCYVJLUPJJJ2TNEBD/
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/XXM224OLGI6KAOROLDPPGGCZ2OQVQ6HH/
https://www.openwall.com/lists/oss-security/2021/01/29/2Exploit, Mailing List, Third Party Advisory
https://www.x41-dsec.de/lab/advisories/x41-2021-001-yara/Exploit, Third Party Advisory
https://bugzilla.redhat.com/show_bug.cgi?id=1930175Issue Tracking, Third Party Advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/FKNXSH5ERG6NELTXCYVJLUPJJJ2TNEBD/
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/XXM224OLGI6KAOROLDPPGGCZ2OQVQ6HH/
https://www.openwall.com/lists/oss-security/2021/01/29/2Exploit, Mailing List, Third Party Advisory
https://www.x41-dsec.de/lab/advisories/x41-2021-001-yara/Exploit, Third Party Advisory

Timeline

Published: May 14, 2021
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2021-3402?

How severe is CVE-2021-3402?

CVE-2021-3402 has a CVSS score of 9.1/10 (CRITICAL severity). The EPSS model estimates a 2.22% probability of exploitation in the next 30 days.

How do I fix CVE-2021-3402?

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-2021-3402?

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

Scan your code now

Source: NVD / NIST