Out-of-bounds Write Affecting upx package, versions <5.0.0-r0


Severity

Recommended
0.0
medium
0
10

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Threat Intelligence

EPSS
0.39% (32nd percentile)

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  • Snyk IDSNYK-WOLFILATEST-UPX-15421688
  • published5 Mar 2026
  • disclosed12 Jan 2023

Introduced: 12 Jan 2023

CVE-2023-23456  (opens in a new tab)
CWE-787  (opens in a new tab)

How to fix?

Upgrade Wolfi upx to version 5.0.0-r0 or higher.

NVD Description

Note: Versions mentioned in the description apply only to the upstream upx package and not the upx package as distributed by Wolfi. See How to fix? for Wolfi relevant fixed versions and status.

A heap-based buffer overflow issue was discovered in UPX in PackTmt::pack() in p_tmt.cpp file. The flow allows an attacker to cause a denial of service (abort) via a crafted file.

CVSS Base Scores

version 3.1