#VU106970 Heap-based buffer overflow in XZ Utils - CVE-2025-31115

Vulnerability identifier: #VU106970

Vulnerability risk: High

CVSSv4.0: 6.1 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Amber]

CVE-ID: CVE-2025-31115

CWE-ID: CWE-122

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
XZ Utils
Universal components / Libraries / Libraries used by multiple products

Vendor: tukaani.org

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 lzma_stream_decoder_mt() function. A remote attacker can pass specially crafted data to the application, trigger a heap-based buffer overflow and execute arbitrary code on the target system.

Successful exploitation of this vulnerability may result in complete compromise of vulnerable system.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

XZ Utils: 5.3.3 alpha - 5.8.0

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External links
https://github.com/tukaani-project/xz/commit/d5a2ffe41bb77b918a8c96084885d4dbe4bf6480
https://github.com/tukaani-project/xz/security/advisories/GHSA-6cc8-p5mm-29w2
https://tukaani.org/xz/xz-cve-2025-31115.patch

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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.