Raw vector
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:XSummary
CVE-2026-8398 is a critical-severity Embedded Malicious Code (CWE-506) vulnerability in Disc-Soft Daemon Tools. Its CVSS base score is 9.3 (Critical).
Operationally, exploitation aligns with the MITRE ATT&CK technique Embedded Payloads (T1027.009); ranked in the top 29% of CVEs by exploit likelihood; CISA has added it to the Known Exploited Vulnerabilities catalog; a public proof-of-concept is referenced.
The strongest mitigations our analysis identified map to SA-11 (Developer Testing and Evaluation) and SC-44 (Detonation Chambers) — see the control section below for these in your framework.
Deeper analysis AI-assisted summary
Synthesised by an AI model from the NVD description and linked references — a reading aid, not an authoritative source.
A supply chain attack compromised the official installation packages of DAEMON Tools Lite for Windows, specifically versions 12.5.0.2421 through 12.5.0.2434, distributed from daemon-tools.cc between April 8 and May 5, 2026. Attackers accessed the vendor AVB Disc Soft's build or distribution infrastructure and inserted malicious code into three binaries—DTHelper.exe, DiscSoftBusServiceLite.exe, and DTShellHlp.exe—which retained valid digital signatures from the vendor's code-signing certificate. The issue is tracked as CVE-2026-8398 with a CVSS 4.0 score of 9.3 and is classified under CWE-506 for embedded malicious code.
Users who downloaded and installed the affected packages from the legitimate site received trojanized executables that could execute arbitrary code with high impact on confidentiality, integrity, and availability. Because the files carried trusted signatures, signature-based detection mechanisms were bypassed, enabling the backdoor to persist on victim systems without immediate detection.
Vendor and third-party advisories, including the official Daemon Tools security incident notice and CISA's Known Exploited Vulnerabilities catalog, list the affected versions and direct users to verify installer integrity or obtain clean copies from updated distribution channels. The Kaspersky analysis further documents the backdoor behavior observed in the trojanized binaries.
The EPSS score for this CVE rose from lower values to a peak of 0.3302 on May 28, 2026, before receding to the current 0.1439, indicating a clear post-disclosure increase in exploitation interest that warrants renewed attention from defenders.
OWASP Top 10 for Web (2025)
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2026-30514
Vulnerability Data
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…
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(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.
- CWE(s)
- KEV Date Added
- 27 May 2026
Related Threats
MITRE ATT&CK Enterprise Techniques
CVEs Like This One
Affected Assets
Mitigating Controls
Control response
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- 3 hardening rules · 2 OS baselines
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Mitigating Controls (NIST 800-53 r5) AI
Developer testing and evaluation can discover embedded malicious code before release.
Detonation chambers can reveal embedded malicious code through controlled execution analysis.
Integrity verification tools directly detect unauthorized or malicious code insertions.
Tamper-resistance and detection mechanisms identify malicious code introduced via the supply chain.
Component authenticity requirements reduce the chance malicious code is embedded by developers or suppliers.
Component authenticity controls stop introduction of malicious or counterfeit code into the product.
Mitigating Controls (NIST CSF 2.0) AI
Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.
Assessing authenticity and integrity before acquisition catches embedded malicious code.
Secure SDLC practices directly prevent introduction of malicious code during development.
Due diligence prior to supplier relationships helps avoid sources of embedded malicious code.
Supplier risk assessment reduces likelihood of receiving products containing malicious code.
Pre-acquisition assessment of critical suppliers mitigates risk of malicious code in procured software.
Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI
Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.
Requiring suppliers to furnish component lists, attestations, and cryptographic verification of delivered artefacts makes it harder for an attacker to embed hidden malicious code that would otherwise go undetected through the supply chain.
Checks that executed code has not been tampered with and monitoring for malware-associated activity reduce the likelihood that hidden malicious code remains active.
Banning unapproved or unknown software and requiring testing plus authorization reduces the chance that hidden malicious code will be introduced into production environments.
Hardening callouts derived
Configuration rules from DISA STIG baselines that bear on weaknesses of the type cited by this CVE. Each rule is shown with the relationship its mapping actually records, against the CWE it was authored against. Derived via CVE→CWE over `controls_xwalks` (authoritative rows only; rows rated `none` are excluded).
Oracle Linux 9 (1 rule)
- V-271452 OL 9 must use a Linux Security Module configured to enforce limits on system services. prevents CWE-506
RHEL 9 (1 rule)
- V-258078 RHEL 9 must use a Linux Security Module configured to enforce limits on system services. prevents CWE-506