CVE-2021-33844Public exploit

Application crash via unchecked bits-per-sample divisor

Published Aug 25, 2022 · Updated Aug 3, 2024

Divide-by-zero in SoX allows attackers to crash an application by processing a crafted WAV file through its audio reader. The startread() function in wav.c passes the WAV header's bits-per-sample value to a sample-count division without rejecting zero. Opening or converting the file is required, and the resulting floating-point exception terminates the affected SoX process without reported data disclosure or modification.

CVSS severity5.5
Medium
EPSS probability0.48%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Divide-by-zero in SoX allows attackers to crash an application by processing a crafted WAV file through its audio reader. The startread() function in wav.c passes the WAV header's bits-per-sample value to a sample-count division without rejecting zero. Opening or converting the file is required, and the resulting floating-point exception terminates the affected SoX process without reported data disclosure or modification.

The record

CVE
CVE-2021-33844
Published
Aug 25, 2022
Updated
Aug 3, 2024
Vendor
Chris Bagwell
Product
SoX
Classifications
CWE-369, T1204.002
Attack vector
local
Privileges
unauthenticated

Timeline

How it unfolded

  1. Aug 25, 2022CVE publishedPublication date reported by the CVE source.
  2. Aug 3, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

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  1. Affected versionversion=Not Known

What conditions does exploitation require?

Attack vectorlocal
Required privilegesunauthenticated

What is affected?

Chris Bagwell · SoXversion=Not Known

Published CVSS scores

3.3SUSECVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:L
5.5NIST NVDCVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-369Divide By Zero
T1204.002Malicious File

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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