CVE-2026-23988Public exploit

Administrator code execution via Fido script replacement

Published Jan 22, 2026 · Updated Jan 22, 2026

TOCTOU race in Akeo Consulting Rufus 4.11 and earlier allows local users to execute arbitrary code as Administrator. DownloadISOThread closes the writable %TEMP% Fido PowerShell script, validates the on-disk file, and later passes its path to RunCommand without preventing replacement. A standard user on the same Windows host must win the write-to-execution race while Rufus runs elevated and initiates a Fido download.

CVSS severity7.3
High
EPSS probability0.20%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

TOCTOU race in Akeo Consulting Rufus 4.11 and earlier allows local users to execute arbitrary code as Administrator. DownloadISOThread closes the writable %TEMP% Fido PowerShell script, validates the on-disk file, and later passes its path to RunCommand without preventing replacement. A standard user on the same Windows host must win the write-to-execution race while Rufus runs elevated and initiates a Fido download.

The record

CVE
CVE-2026-23988
Published
Jan 22, 2026
Updated
Jan 22, 2026
Vendor
Akeo Consulting
Product
Rufus
Classifications
CWE-367, T1068
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. Jan 22, 2026CVE publishedPublication date reported by the CVE source.
  2. Jan 22, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=< 4.12_BETA

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

Akeo Consulting · Rufusversion=< 4.12_BETA

Published CVSS scores

7.3GitHubCVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:H
7.0NIST NVDCVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-367Time-of-check Time-of-use (TOCTOU) Race Condition
T1068Exploitation for Privilege Escalation

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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