CVE-2026-8398
Daemon Tools Lite Embedded Malicious Code Vulnerability
Daemon Tools Lite
A supply chain attack compromised the official installation packages of DAEMON Tools Lite (Windows versions 12.5.0.2421 through 12.5.0.2434), distributed from the legitimate website daemon-tools.cc between approximately April 8, 2026, and May 5, 2026. Attackers gained unauthorized access to the vendor's (AVB Disc Soft) build or distribution infrastructure and trojanized three binaries: DTHelper.exe, DiscSoftBusServiceLite.exe, and DTShellHlp.exe. These files were digitally signed with the legitimate AVB Disc Soft code-signing certificate, allowing the malicious installers to appear trustworthy and bypass signature-based detection.
Exploitation status
CISA Known Exploited Vulnerabilities
Listed by CISA on 27 May 2026. US federal agencies were required to remediate it by 30 May 2026.
EPSS — exploitation probability
FIRST puts the probability of exploitation activity in the next 30 days at 1.5%, which is higher than 71% of all scored vulnerabilities. EPSS is a forecast of activity, not a measure of severity, and it is rescored daily.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Frequently asked questions
Is CVE-2026-8398 being exploited by ransomware groups?
No ransomware group in this database is currently recorded as exploiting CVE-2026-8398.
What does CVE-2026-8398 affect?
CVE-2026-8398 affects Daemon Tools Lite. A supply chain attack compromised the official installation packages of DAEMON Tools Lite (Windows versions 12.5.0.2421 through 12.5.0.2434), distributed from the legitimate website daemon-tools.cc between approximately April 8, 2026, and May 5, 2026. Attackers gained unauthorized access to the vendor's (AVB Disc Soft) build or distribution infrastructure and trojanized three binaries: DTHelper.exe, DiscSoftBusServiceLite.exe, and DTShellHlp.exe. These files were digitally signed with the legitimate AVB Disc Soft code-signing certificate, allowing the malicious installers to appear trustworthy and bypass signature-based detection.
How severe is CVE-2026-8398?
CVE-2026-8398 is rated CRITICAL with a CVSS base score of 9.8. EPSS puts the probability of exploitation in the next 30 days at 1.5%, higher than 71% of all scored vulnerabilities. It is listed in the CISA Known Exploited Vulnerabilities catalog, with a federal remediation deadline of 30 May 2026.
How should organisations respond to CVE-2026-8398?
Apply the vendor patch for Daemon Tools Lite as the first priority, and treat any internet-facing instance as the most urgent. Because this vulnerability is associated with ransomware activity, also review whether the affected systems were reachable before patching, rather than assuming that patching alone closes the incident.