CVE-2015-6997: Apple iPhone OS

Medium severity, CVSS 4.3. EPSS: 0.9% chance of exploitation in the next 30 days.

The X.509 certificate-trust implementation in Apple iOS before 9.1 does not recognize that the kSecRevocationRequirePositiveResponse flag implies a revocation-checking requirement, which makes it easier for man-in-the-middle attackers to spoof endpoints by leveraging access to a revoked certificate.

Affected products

• Apple iPhone OS: up to and including 9.0.2
• Apple watchOS: up to and including 2.0

Published 2015-10-23. Last modified 2026-06-17.