NULL pointer dereference in zsh - CVE-2018-7548

 

NULL pointer dereference in zsh - CVE-2018-7548

Published: March 7, 2018


Vulnerability identifier: #VU10873
CSH Severity: Low
CVSS v4: 4.8 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N]
CVE-ID: CVE-2018-7548
CWE-ID: CWE-476
Exploitation vector: Local access
Exploit availability: No public exploit available

Vulnerability details

The vulnerability allows a local attacker to cause DoS condition on the target system.

The weakness exists in the subst.c source code file due to a NULL pointer dereference. A local attacker can implement ${(PA)...} characters on an empty array result, trigger a NULL pointer dereference condition and cause the service to crash.

Affected software

zsh
Arch Linux
Gentoo Linux
Slackware Linux
Fedora
zsh

How to mitigate CVE-2018-7548

Install update from vendor's website.

zsh - addressed in versions 5.3.1-7.fc26, 5.4.1-2.fc27, 5.4.2-7.fc28

External References

Related Security Bulletins