#VU15789 UNIX symbolic link following in Keepalived - CVE-2018-19044

Vulnerability identifier: #VU15789

Vulnerability risk: Low

CVSSv4.0: 0.4 [CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2018-19044

CWE-ID: CWE-61

Exploitation vector: Local

Exploit availability: No

Vulnerable software:
Keepalived
Server applications / Other server solutions

Vendor: Keepalived

Description

The vulnerability allows a local user to escalate privileges on the system.

The vulnerability exists due to a symlink following issue when writing data to a temporary file upon a call to PrintData or PrintStats. A local user can create a specially crafted symbolic link to a critical file on the system and overwrite it with privileges of the application, if fs.protected_symlinks is set to 0.

Successful exploitation of this vulnerability may result in privilege escalation.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Keepalived: 2.0.8

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External links
https://bugzilla.suse.com/show_bug.cgi?id=1015141
https://github.com/acassen/keepalived/commit/04f2d32871bb3b11d7dc024039952f2fe2750306
https://github.com/acassen/keepalived/issues/1048

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Q & A

Can this vulnerability be exploited remotely?

No. This vulnerability can be exploited locally. The attacker should have authentication credentials and successfully authenticate on the system.

Is there known malware, which exploits this vulnerability?

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