Heap-based Buffer Overflow Affecting upx package, versions [,4.2.1)


Severity

Recommended
0.0
high
0
10

CVSS assessment by Snyk's Security Team. Learn more

Threat Intelligence

Exploit Maturity
Proof of Concept
EPSS
0.39% (31st percentile)

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  • Snyk IDSNYK-CONAN-UPX-10078466
  • published8 May 2025
  • disclosed13 Jan 2023
  • creditsuper_maggie

Introduced: 13 Jan 2023

CVE-2023-23456  (opens in a new tab)
CWE-122  (opens in a new tab)

How to fix?

Upgrade upx to version 4.2.1 or higher.

Overview

Affected versions of this package are vulnerable to Heap-based Buffer Overflow via the PackTmt::pack() function in the p_tmt.cpp file. The flow allows an attacker to cause an abort via a crafted file.

CVSS Base Scores

version 3.1