#VU106281 Heap-based buffer overflow in UPX - CVE-2025-2849

Vulnerability identifier: #VU106281

Vulnerability risk: Medium

CVSSv4.0: 4 [CVSS:4.0/AV:L/AC:H/AT:N/PR:N/UI:A/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2025-2849

CWE-ID: CWE-122

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
UPX
Universal components / Libraries / Libraries used by multiple products

Vendor: UPX

Description

The vulnerability allows a remote attacker to execute arbitrary code on the target system.

The vulnerability exists due to a boundary error within the PackLinuxElf64::un_DT_INIT() function in p_lx_elf.cpp. A remote attacker can trick the victim into using a specially crafted file, trigger a heap-based buffer overflow and execute arbitrary code on the target system.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

UPX: 1.10 - 5.0.0

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External links
https://github.com/upx/upx/commit/e0b6ff192412f5bb5364c1948f4f6b27a0cd5ea2
https://github.com/upx/upx/issues/898

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Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.