Vulnerability identifier: #VU32031

Vulnerability risk: Medium

CVSSv3.1: 4.6 [CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N/E:U/RL:O/RC:C]

CVE-ID: CVE-2018-18586

CWE-ID: CWE-22

Exploitation vector: Network

Exploit availability: No

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

Vendor: Stuart Caie

Description

The vulnerability allows a remote non-authenticated attacker to gain access to sensitive information.

** DISPUTED ** chmextract.c in the chmextract sample program, as distributed with libmspack before 0.8alpha, does not protect against absolute/relative pathnames in CHM files, leading to Directory Traversal. NOTE: the vendor disputes that this is a libmspack vulnerability, because chmextract.c was only intended as a source-code example, not a supported application.

Mitigation
Install update from vendor's website.

Vulnerable software versions

libmspack: 0.0.20060920alpha - 0.7alpha

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External links
http://bugs.debian.org/911639
http://github.com/kyz/libmspack/commit/7cadd489698be117c47efcadd742651594429e6d
http://security.gentoo.org/glsa/201903-20
http://www.openwall.com/lists/oss-security/2018/10/22/1

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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.