#VU79707 Out-of-bounds write in Bzip3 - CVE-2023-29421

Vulnerability identifier: #VU79707

Vulnerability risk: High

CVSSv4.0: 8.1 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Amber]

CVE-ID: CVE-2023-29421

CWE-ID: CWE-787

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
Bzip3
Universal components / Libraries / Libraries used by multiple products

Vendor: Bzip3 Project

Description

The vulnerability allows a remote attacker to compromise vulnerable system.

The vulnerability exists due to a boundary error within the bz3_decode_block() function in libbzip3.a. A remote attacker can trigger an out-of-bounds write and execute arbitrary code on the target system.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Bzip3: 1.0.0 - 1.2.2

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External links
https://github.com/kspalaiologos/bzip3/compare/1.2.2...1.2.3
https://github.com/kspalaiologos/bzip3/issues/94
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/NA7S7HDUAINOTCSWQZ5LIW756DYY22V2/
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/4JLSE25SV7K2NB6FTFT4UHJOJUHBHYHY/
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/NMLFV2FJK3CM7NJLVPZI5RUAFQZICPWW/

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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.