CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Called exploited 7 days before disclosure.
Measured from the CVE publication date to the earliest of 3 KEV catalogues that list it.
The life of this vulnerability
- CVE published
- First KEV listing7d
- Last KEV listing19d
- Last sightingsame day
Gaps are compressed to equal steps. The elapsed time is printed under each.
Which catalogues call it exploited
- CISA KEVUS federallisted May 27, 2026
- EUVDENISA, European Unionlisted May 27, 2026
- VulnCheck KEVcommercial researchlisted May 8, 2026
- CIRCLaggregator, mirrors the abovelisted May 27, 2026, not counted
3 catalogues list it. CIRCL aggregates the others and is shown but not counted.
Public exploitation evidence
- reported exploitationvulnerability.circl.lu/known-exploited-vulnerabilities-catal
- reported exploitationwww.cisa.gov/sites/default/files/feeds/known_exploited_vulne
- reported exploitationsecurelist.com/tr/daemon-tools-backdoor/119654/
3 public reports collected from VulnCheck and CIRCL, first on May 8, 2026. Each links to its original source. We have not verified them.
Description
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.
Required action (CISA)
Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.