VulnerabilityAnalyzed

CVE-2026-23988

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.

HIGH 7.0EPSS 0.20%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (0.20%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.

Description

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: 7.0 HIGHCVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H
EPSS: 0.20% probability · 9th percentile
CISA KEV: Not listed
Weakness: CWE-367
Affected: akeo/rufus
Source: security-advisories@github.com

References

https://github.com/pbatard/rufus/commit/460cc5768aa45be07941b9e4ebc9bee02d282873Patch
https://github.com/pbatard/rufus/releases/tag/v4.12_BETABroken Link
https://github.com/pbatard/rufus/security/advisories/GHSA-hcx5-hrhj-xhq9Exploit, Vendor Advisory

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.