#VU41857 Input validation error in Xen - CVE-2014-1891

Vulnerability identifier: #VU41857

Vulnerability risk: Low

CVSSv4.0: 4.3 [CVSS:4.0/AV:A/AC:L/AT:N/PR:H/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2014-1891

CWE-ID: CWE-20

Exploitation vector: Local network

Exploit availability: No

Vulnerable software:
Xen
Server applications / Virtualization software

Vendor: Xen Project

Description

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

Multiple integer overflows in the (1) FLASK_GETBOOL, (2) FLASK_SETBOOL, (3) FLASK_USER, and (4) FLASK_CONTEXT_TO_SID suboperations in the flask hypercall in Xen 4.3.x, 4.2.x, 4.1.x, 3.2.x, and earlier, when XSM is enabled, allow local users to cause a denial of service (processor fault) via unspecified vectors, a different vulnerability than CVE-2014-1892, CVE-2014-1893, and CVE-2014-1894.

Mitigation
Install update from vendor's website.

Vulnerable software versions

Xen: 3.2.0 - 4.3.1

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External links
https://lists.opensuse.org/opensuse-security-announce/2014-03/msg00010.html
https://lists.opensuse.org/opensuse-security-announce/2014-03/msg00011.html
https://lists.opensuse.org/opensuse-security-announce/2014-03/msg00021.html
https://security.gentoo.org/glsa/glsa-201407-03.xml
https://www.openwall.com/lists/oss-security/2014/02/07/12
https://www.openwall.com/lists/oss-security/2014/02/07/4
https://www.openwall.com/lists/oss-security/2014/02/10/8
https://xenbits.xen.org/xsa/advisory-84.html

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Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote authenticated privileged user via the local network (LAN).

Is there known malware, which exploits this vulnerability?

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