#VU18051 Input validation error in UnZip - CVE-2016-9844

Vulnerability identifier: #VU18051

Vulnerability risk: Medium

CVSSv4.0: 5.2 [CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:P/U:Green]

CVE-ID: CVE-2016-9844

CWE-ID: CWE-20

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
UnZip
Client/Desktop applications / Software for archiving

Vendor: Info-ZIP

Description

The vulnerability allows a remote attacker to perform a denial of service (DoS) attack.

The vulnerability exists due to insufficient validation of user-supplied input in the zi_short() function in zipinfo.c when processing a large compression method value in the central directory file header. A remote attacker can pass a specially crafted array to the application and trigger denial of service (DoS) condition.

Mitigation
Cybersecurity Help is currently unaware of any official solution to address this vulnerability.

Vulnerable software versions

UnZip: 6.0

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External links
https://www.openwall.com/lists/oss-security/2016/12/05/13
https://www.openwall.com/lists/oss-security/2016/12/05/19
https://www.openwall.com/lists/oss-security/2016/12/05/20
https://www.securityfocus.com/bid/94728
https://bugs.launchpad.net/ubuntu/+source/unzip/+bug/1643750

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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. However, proof of concept for this vulnerability is available.