CVE-2026-8398: Daemon Tools Lite Embedded Malicious Code Vulnerability

Should you act?

Exploited: patch now if you run it

CISA has confirmed exploitation in the wild. This signal is computed from CISA KEV, EPSS and CVSS data; it is not an editorial verdict.

• Yes, if you run Daemon Daemon Tools Lite. CISA added this CVE to its Known Exploited Vulnerabilities catalog on 2026-05-27, which means there is reliable evidence of exploitation in the wild. US federal agencies must remediate by 2026-05-30; treat that as the outer limit, not the target.
• EPSS 1.0%, percentile 61: FIRST’s model estimates a 1.0% chance of exploitation activity in the next 30 days, higher than 61% of all scored CVEs (moderate). EPSS is a probability, not a verdict.
• Remotely reachable with no login and no user interaction. If the vulnerable service is exposed to the internet, prioritize it.

What it is

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.

CISA’s summary

Daemon Tools contains an unspecified vulnerability that has a high impact on confidentiality, integrity, and availability.

Weakness type: CWE-506.

Product: Daemon Daemon Tools Lite · Assigned by: Kaspersky · Published: 2026-05-15

Affected and fixed versions

Severity scores

• Attack vector: network (remotely reachable)
• Attack complexity: low
• Attack requirements: none
• Privileges required: none (no login)
• User interaction: none

CVSS measures how bad a flaw is if exploited, not how likely exploitation is. Read it next to the exploitation data below.

Exploitation and urgency

• CISA KEV: added 2026-05-27; federal due date 2026-05-30. Known ransomware use: Unknown.
• CISA required action: Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.
• CISA SSVC assessment: exploitation active, automatable yes, technical impact total.
• FIRST EPSS (model of 2026-10-21): 0.96% probability of exploitation activity in the next 30 days; percentile 61.

Timeline

• 2026-05-15 — CVE record published by Kaspersky
• 2026-05-27 — Added to CISA’s Known Exploited Vulnerabilities catalog
• 2026-05-28 — CVE record last updated
• 2026-05-30 — CISA remediation deadline for US federal agencies

Sources and references

Original sources first. Version and fix details should always be confirmed against the vendor or project advisory.

Vendor and project advisories, patches

1. Security Incident Affecting DAEMON Tools Lite: What We Know So Far blog.daemon-tools.cc

Vulnerability records

1. CVE.org record CVE-2026-8398 cve.org
2. NVD entry CVE-2026-8398 nvd.nist.gov

Government

1. CISA Known Exploited Vulnerabilities catalog entry cisa.gov

Other references from the CVE record and advisory

1. DAEMON Tools software infected – supply chain attack ongoing since April 8, 2026 securelist.com

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