SB2018090802 - Authorization bypass in zsh 

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Main Vulnerability Database SB2018090802

SB2018090802 - Authorization bypass in zsh

Published: September 8, 2018

Security Bulletin ID SB2018090802
Severity
Low
Patch available
YES
Number of vulnerabilities 2
Exploitation vector Local access
Highest impact Code execution

Breakdown by Severity

Low 100%
  • Low
  • Medium
  • High
  • Critical

Description

This security bulletin contains information about 2 secuirty vulnerabilities.


1) Authorization bypass (CVE-ID: CVE-2018-13259)

The vulnerability allows a local attacker to execute a program without proper authorization on the target system.

The vulnerability exists due to improper truncating of shebang (#!) lines that exceed 64 characters. A local attacker can access the shell and submit a shebang line longer than 64 characters, cause the software to make an execve() call to a program name that is a substring of the intended one and execute a program without proper authorization on the system.


2) Authorization bypass (CVE-ID: CVE-2018-0502)

The vulnerability allows a local attacker to execute a program without proper authorization on the target system.

The vulnerability exists due to improper handling of the beginning of a shebang (#!) script file. A local attacker can execute a shebang script file that submits malicious input, pass content from the second line of the file to execve() and execute a program without proper authorization on the system. 


Remediation

Install update from vendor's website.

References