Rufus has Local Privilege Escalation via TOCTOU Race Condition in Fido Script Handling
21Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 7.3epss 0.2%
exploitation probability
0.2%top 90% of all CVEs
observed exploitation
nono source reports it
Rufus is a utility that helps format and create bootable USB flash drives. Versions 4.11 and below contain a race condition (TOCTOU) in src/net.c during the creation, validation, and execution of the Fido PowerShell script. Since Rufus runs with elevated privileges (Administrator) but writes the script to the %TEMP% directory (writeable by standard users) without locking the file, a local attacker can replace the legitimate script with a malicious one between the file write operation and the execution step. This allows arbitrary code execution with Administrator privileges. This issue has been fixed in version 4.12_BETA.
CVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:H
Affected products
pbatard · rufus