CVE-2026-23988 (GCVE-0-2026-23988)

Vulnerability from cvelistv5 – Published: 2026-01-22 21:52 – Updated: 2026-01-23 20:13
VLAI
Title
Rufus has Local Privilege Escalation via TOCTOU Race Condition in Fido Script Handling
Summary
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.
Severity
7.3 (High)
CVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:H
SSVC
Exploitation: poc Automatable: no Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-01-23 20:13 UTC
CWE
  • CWE-367 - Time-of-check Time-of-use (TOCTOU) Race Condition
Assigner
GitHub_M CNA
References
Impacted products
Vendor Product Version
pbatard rufus Affected: < 4.12_BETA
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