CVE-2023-39741Public exploit

Process crash via postprocessor heap overwrite

Published Aug 17, 2023 · Updated Oct 8, 2024

Heap overflow in lrzip 0.651 allows attackers to crash the process by having it test or decompress a crafted archive. While loading postprocessor program bytes, libzpaq::PostProcessor::write(int) appends an attacker-controlled byte past the end of its allocated header array. A user must cause lrzip to process the file; the demonstrated result is an AddressSanitizer abort, with no reported confidentiality or integrity impact.

CVSS severity5.5
Medium
EPSS probability0.35%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Heap overflow in lrzip 0.651 allows attackers to crash the process by having it test or decompress a crafted archive. While loading postprocessor program bytes, libzpaq::PostProcessor::write(int) appends an attacker-controlled byte past the end of its allocated header array. A user must cause lrzip to process the file; the demonstrated result is an AddressSanitizer abort, with no reported confidentiality or integrity impact.

The record

CVE
CVE-2023-39741
Published
Aug 17, 2023
Updated
Oct 8, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-787, T1204.002
Attack vector
local
Privileges
unauthenticated

Timeline

How it unfolded

  1. Aug 17, 2023CVE publishedPublication date reported by the CVE source.
  2. Oct 8, 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?

Affected buildAffected product and version details are unavailable.

What conditions does exploitation require?

Attack vectorlocal
Required privilegesunauthenticated

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

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-787Out-of-bounds Write
T1204.002User Execution: Malicious 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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