YARA up to 4.0.3 Mach-O File macho.c buffer overflow

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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A vulnerability was found in YARA up to 4.0.3. It has been rated as critical. This issue affects an unknown code block of the file libyara/modules/macho/macho.c of the component Mach-O File Handler. The manipulation with an unknown input leads to a memory corruption vulnerability. Using CWE to declare the problem leads to CWE-120. Impacted is confidentiality, integrity, and availability. The summary by CVE is:

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

The weakness was shared 05/15/2021. The advisory is shared at bugzilla.redhat.com. The identification of this vulnerability is CVE-2021-3402 since 02/08/2021. The exploitation is known to be easy. Access to the local network is required for this attack. The requirement for exploitation is a simple authentication. Technical details are known, but no exploit is available.

Upgrading to version 4.0.4 eliminates this vulnerability.



CPE 2.3infoedit

CPE 2.2infoedit


VulDB Meta Base Score: 5.5
VulDB Meta Temp Score: 5.3

VulDB Base Score: 5.5
VulDB Temp Score: 5.3
VulDB Vector: 🔒
VulDB Reliability: 🔍



VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍


Class: Memory corruption
CWE: CWE-120
ATT&CK: Unknown

Local: No
Remote: Partially

Availability: 🔒
Status: Not defined

Price Prediction: 🔍
Current Price Estimation: 🔒


Threat Intelligenceinfoedit

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍


Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: YARA 4.0.4


02/08/2021 CVE assigned
05/15/2021 +95 days Advisory disclosed
05/15/2021 +0 days VulDB entry created
05/20/2021 +4 days VulDB last update


Advisory: bugzilla.redhat.com
Status: Confirmed

CVE: CVE-2021-3402 (🔒)


Created: 05/15/2021 06:29 PM
Updated: 05/20/2021 01:46 AM
Changes: (5) source_cve_assigned source_cve_nvd_summary vulnerability_cvss2_vuldb_tempscore vulnerability_cvss3_vuldb_tempscore vulnerability_cvss3_meta_tempscore
Complete: 🔍


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