Description
pam_usb provides hardware authentication for Linux using ordinary removable media. Prior to 0.8.7, src/tmux.c reads the user's $TMUX environment variable, splits it on commas, and interpolates the socket-path component directly into a shell command passed to popen(). Because the value is placed inside double-quotes without sanitisation, any value containing " terminates the quoted string and injects arbitrary shell syntax. popen() runs as root inside the PAM stack. This vulnerability is fixed in 0.8.7.
CVSS breakdown
CVSS 3.1
Attack Vector
Local
Attack Complexity
Low
Privileges Required
Low
User Interaction
None
Scope
Changed
Confidentiality
High
Integrity
High
Availability
High
Affected products
- mcdope / pam_usb< 0.8.7 – < 0.8.7