NVD / CVE Program· CNA mitre

CVE-2021-45429: A Buffer Overflow vulnerablity exists in VirusTotal YARA git commit: 605b2edf07ed8eb9a2c61ba22eb2e7c362f47ba7 via yr_set_configuration in ya

Noroxi assessment

Priority: Monitor (action score 22/100)

The sources we track (CISA KEV, Exploit-DB, Metasploit, Nuclei, GitHub) show no public exploit code or exploitation in the wild.
Probability of exploitation in the next 30 days: 0.83% (FIRST EPSS); higher than 57.7% of all records.
Someone with local access to the system can trigger it. No account or password is required. A user must open a link or visit a page. No special conditions are required; it is repeatable.
Fixed version: yara (Alpine:v3.19) 4.2.0-r0; yara (Debian:12) 4.2.0-1.

Low priority for now. Upgrade to yara (Alpine:v3.19) 4.2.0-r0; yara (Debian:12) 4.2.0-1 or later.

Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it

Primary sources: NVD · CVE.org · FIRST EPSS

A Buffer Overflow vulnerablity exists in VirusTotal YARA git commit: 605b2edf07ed8eb9a2c61ba22eb2e7c362f47ba7 via yr_set_configuration in yara/libyara/libyara.c, which could cause a Denial of Service.

MediumCVSS 5.5 · v3.1—No exploit Fix available

Published: Feb 4, 2022
Updated: Jun 17, 2026
EPSS: 0.8% · 57th percentile
CWE: CWE-120

Report tools

JSON

Action score

Monitor

Low priority for now.

CVSS: 22 / 40 · 5.5 / 10
CISA KEV: 0 / 30 · Not listed
EPSS: 0 / 30 · 0.8%

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No public exploit code on record
A fix has been released

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Noroxi analysis

What does it mean in your environment?

The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.

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Affected systems

Is your version affected?

Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.

Vendor	Product	CPE
virustotal	yara	cpe:2.3:a:virustotal:yara

Affected versions

NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.

virustotal yaraup to 4.1.3 inclusive

Package-level exposure

OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.

Ecosystem	Package	Affected range	Fix
Alpine:v3.19	yara	before 4.2.0-r0	4.2.0-r0
Debian:12	yara	before 4.2.0-1	4.2.0-1

Same product

virustotal: all records

Other highest-scoring records for the same primary product.

CVE-2021-3402An 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
37Monitor
CVE-2023-40857Buffer Overflow vulnerability in VirusTotal yara v.4.3.2 allows a remote attacker to execute arbtirary code via the yr_execute_cod function
35Monitor
CVE-2019-19648In the macho_parse_file functionality in macho/macho.c of YARA 3.11.0, command_size may be inconsistent with the real size.
31Monitor

Published before and after this one in the same product

← EarlierCVE-2018-19975Dec 17, 2018 · In YARA 3.8.1, bytecode in a specially crafted compiled rule can read data from any arbitrary address in memory, in libyara/exec.c.
22Monitor
← EarlierCVE-2018-19976Dec 17, 2018 · In YARA 3.8.1, bytecode in a specially crafted compiled rule is exposed to information about its environment, in libyara/exec.c.
22Monitor
← EarlierCVE-2019-5020Jul 31, 2019 · An exploitable denial of service vulnerability exists in the object lookup functionality of Yara 3.8.1.
22Monitor

Remediation

Which version to upgrade to

Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.

Product / package	Fixed version	Source
alpine:yara	4.2.0-r0 · Alpine:v3.19	Package registry (OSV)
debian:yara	4.2.0-1 · Debian:12	Package registry (OSV)

Exploit status

No known public exploit

No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.

Research context

For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.

Timeline

From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.

No dated events beyond publication.

No history yet (it accumulates with the daily EPSS job).

Patch and commit links

Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.

No commit or PR link among the references.

Credits

All researchers

Finders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.

No credits in the CNA record.

Variant candidates

Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.

No nightly-computed relations.

Chain candidates

An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.

—

Bug bounty scope

No known public program.

Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).

Technical details

Attack conditions

Someone with local access to the system can trigger it.
No account or password is required.
A user must open a link or visit a page.
No special conditions are required; it is repeatable.

If successful

Confidentiality: none
Integrity: none
Availability: high · the service can be disrupted

Attack vector: Local
Attack complexity: Low
Privileges required: None
User interaction: Required
Scope: Unchanged
Confidentiality impact: None
Integrity impact: None
Availability impact: High

Weakness class (CWE)

CWE-120 · Buffer Copy without Checking Size of Input ('Classic Buffer Overflow')

CVSS vector

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

nvd-primary

Root cause

When data is copied, the source length is not compared with the size of the destination buffer. Excess data overwrites adjacent memory.

The bug in code

The whole CWE-120 class

A representative example of this vulnerability class. Not the vendor's source code; it shows the faulty pattern and its fix.

Vulnerable

1char buf[256];
2memcpy(buf, pkt->data, pkt->len);

Fixed

1char buf[256];
2if (pkt->len > sizeof(buf)) {
3  return -EINVAL;
4}
5memcpy(buf, pkt->data, pkt->len);

Attack context

MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.

Attack patterns (CAPEC)

ATT&CK techniques

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Change log

Fix✗ → ✓Sep 28, 2026, 10:49 PM UTC

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