Permissions, Privileges, and Access Controls in glib (Alpine package)

1) Permissions, Privileges, and Access Controls

EUVDB-ID: #VU18658

Risk: Low

CVSSv3.1: 3.9 [CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:L/I:L/A:L/E:U/RL:O/RC:C]

CVE-ID: CVE-2019-12450

CWE-ID: CWE-264 - Permissions, Privileges, and Access Controls

Exploit availability: No

Description

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

The vulnerability exists due to the application applies default directory permissions to files while copying them in file_copy_fallback() function in gio/gfile.c. A local user can interfere with the copying operation and gain access to otherwise restricted files, as the application applies correct access permissions after the file was copied only.

Such application behavior allows a local user to access potentially sensitive data or modify file contents in case directory permissions that were applied to the file allow such operations.

Mitigation

Install update from vendor's website.

Vulnerable software versions

glib (Alpine package): 2.20.5-r0 - 2.56.1-r0

External links

http://git.alpinelinux.org/aports/commit/?id=77237d49b516317fdea1ebc585c3bbf30f766ff8
http://git.alpinelinux.org/aports/commit/?id=c43990edbd40871044e249a0223d247d11b25d7e
http://git.alpinelinux.org/aports/commit/?id=300c17172f28b6d0bd024111bc74805dc28de56a
http://git.alpinelinux.org/aports/commit/?id=6d61c0096ba308d340d865f9fc295ac6e88e1277
http://git.alpinelinux.org/aports/commit/?id=a59a37b197c56022525bbdcbec2d0b98b048883b
http://git.alpinelinux.org/aports/commit/?id=35653be643e562d3fa63f89a3099278768b789ff

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.