Vulnerability identifier: #VU19263

Vulnerability risk: Low

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

CVE-ID: CVE-2019-12779

CWE-ID: CWE-61

Exploitation vector: Local

Exploit availability: No

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

Vendor: ClusterLabs

Description

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

The vulnerability exists due to a symlink following issue because software uses predictable filenames (under /dev/shm and /tmp) without O_EXCL in libqb before 1.0.5. 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.

Successful exploitation of this vulnerability may result in privilege escalation.

Mitigation
Install update from vendor's website.

Vulnerable software versions

libqb: 0.1.0 - 1.0.4

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External links
http://bugzilla.redhat.com/show_bug.cgi?id=1695948
http://github.com/ClusterLabs/libqb/issues/338
http://github.com/ClusterLabs/libqb/releases/tag/v1.0.4
http://github.com/ClusterLabs/libqb/releases/tag/v1.0.5

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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.