Red Hat update for polkit

1) Command injection

EUVDB-ID: #VU16313

Risk: Low

CVSSv4.0: 7.1 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:P/U:Clear]

CVE-ID: CVE-2018-19788

CWE-ID: CWE-77 - Command injection

Exploit availability: Yes

Description

The vulnerability allows a local authenticated attacker to execute arbitrary commands on the target system.

The vulnerability exists due to PolicyKit's improper validation of permission requests for any low-privileged user with UID greater than INT_MAX, a constant in computer programming that defines what maximum value an integer variable can store, which equals to 2147483647 (in hexadecimal 0x7FFFFFFF). A local authenticated attacker with a uid greater than INT_MAX can execute any systemctl command.

Mitigation

Install updates from vendor's website.

Vulnerable software versions

Red Hat Enterprise Linux for IBM z Systems: 7.6

Red Hat Enterprise Linux for x86_64: 7.6

Red Hat Enterprise Linux for Power: 7.6

CPE2.3

• cpe:2.3:o:red_hat:red_hat_enterprise_linux_for_ibm_z_systems:7.6:*:*:*:*:red_hat_enterprise_linux:*:*
• cpe:2.3:o:red_hat:red_hat_enterprise_linux:7.6:*:*:*:*:*:*:*
• cpe:2.3:o:red_hat:red_hat_enterprise_linux_for_power:7.6:*:*:*:*:red_hat_enterprise_linux:*:*

External links

https://access.redhat.com/errata/RHSA-2019:3232

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. However, proof of concept for this vulnerability is available.