CVE-2026-20631
Published: 25 March 2026
Summary
CVE-2026-20631 is a high-severity an unspecified weakness vulnerability in Apple Macos. Its CVSS base score is 8.8 (High).
Operationally, exploitation aligns with the MITRE ATT&CK technique Exploitation for Privilege Escalation (T1068); ranked at the 21.2th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.
The strongest mitigations our analysis identified are NIST 800-53 AC-3 (Access Enforcement) and SI-2 (Flaw Remediation).
Deeper analysis
CVE-2026-20631 is a logic issue addressed with improved checks in macOS. The vulnerability affects macOS versions prior to Tahoe 26.4 and enables a user to elevate privileges. It has a CVSS v3.1 base score of 8.8 (AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H) and is associated with CWE category NVD-CWE-noinfo.
An attacker with low privileges (PR:L) can exploit this vulnerability over the network (AV:N) with low attack complexity and no user interaction required. Successful exploitation results in high impacts to confidentiality, integrity, and availability, allowing the attacker to elevate privileges.
Apple's security advisory confirms the issue is fixed in macOS Tahoe 26.4. Security practitioners should apply this update to mitigate the vulnerability. Additional details are available at https://support.apple.com/en-us/126794.
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2026-15039
Vulnerability details
A logic issue was addressed with improved checks. This issue is fixed in macOS Tahoe 26.4. A user may be able to elevate privileges.
- CWE(s)
Related Threats
MITRE ATT&CK Enterprise TechniquesAI
Why these techniques?
The CVE describes a logic flaw enabling local privilege escalation from low-privileged user context, directly matching T1068 Exploitation for Privilege Escalation.
CVEs Like This One
Affected Assets
Mitigating Controls
Mitigating Controls (NIST 800-53 r5) AI
Requires timely remediation of software flaws, directly mitigating this logic issue by applying the macOS Tahoe 26.4 patch.
Enforces logical access authorizations with improved checks to prevent unauthorized privilege elevation exploited by this logic flaw.
Implements least privilege to restrict low-privilege users from gaining elevated access, limiting the scope of exploitation.