#VU42415 Permissions, Privileges, and Access Controls in systemd - CVE-2013-4394

Vulnerability identifier: #VU42415

Vulnerability risk: Medium

CVSSv4.0: 4.6 [CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:A/VC:H/VI:H/VA:L/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2013-4394

CWE-ID: CWE-264

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
systemd
Server applications / Other server solutions

Vendor: Freedesktop.org

Description

The vulnerability allows a remote non-authenticated attacker to #BASIC_IMPACT#.

The SetX11Keyboard function in systemd, when PolicyKit Local Authority (PKLA) is used to change the group permissions on the X Keyboard Extension (XKB) layouts description, allows local users in the group to modify the Xorg X11 Server configuration file and possibly gain privileges via vectors involving "special and control characters."

Mitigation
Install update from vendor's website.

Vulnerable software versions

systemd: All versions

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External links
https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=725357
https://www.debian.org/security/2013/dsa-2777
https://www.openwall.com/lists/oss-security/2013/10/01/9
https://bugzilla.redhat.com/show_bug.cgi?id=862324
https://security.gentoo.org/glsa/201612-34

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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.