CVE-2026-0421
Raw vector
CVSS:4.0/AV:L/AC:L/AT:N/PR:H/UI:P/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-2026-0421 is a high-severity Unchecked Return Value (CWE-252) vulnerability in Lenovo (inferred from references). Its CVSS base score is 7.0 (High).
Operationally, exploitation aligns with the MITRE ATT&CK technique Exploitation for Privilege Escalation (T1068); ranked at the 2th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.
The strongest mitigations our analysis identified map to SA-11 (Developer Testing and Evaluation) and SA-15 (Development Process, Standards, and Tools) — see the control section below for these in your framework.
OWASP Top 10 for Web (2025)
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2026-2664
Vulnerability Data
A potential vulnerability was reported in the BIOS of L13 Gen 6, L13 Gen 6 2-in-1, L14 Gen 6, and L16 Gen 2 ThinkPads which could result in Secure Boot being disabled even when configured as “On” in the BIOS…
more
setup menu. This issue only affects systems where Secure Boot is set to User Mode.
- CWE(s)
Related Threats
MITRE ATT&CK Enterprise Techniques
CVEs Like This One
Affected Assets
Mitigating Controls
Mitigating Controls (NIST 800-53 r5) AI
Developer testing and code evaluation can discover instances where return values are ignored.
Requiring a documented development process and coding standards can mandate explicit checking of all function return values.
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.
Secure SDLC practices directly require checking and handling all function return values to detect error conditions.
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.
Security testing in development and acceptance can detect missing return-value checks.
Secure development life cycle mandates verification of return values to prevent undetected failures.
Application security requirements include input/output validation and error handling that covers return-value checks.
Secure system architecture and engineering principles require robust error handling and defensive coding practices.
Secure coding explicitly requires checking return values to avoid CWE-252.