CVE-2025-43185 is a vulnerability identified in Apple macOS prior to the Sequoia 15.6 update. The root cause is a downgrade issue related to code-signing restrictions, which are mechanisms that ensure only trusted applications can access sensitive system resources and user data. In this case, the downgrade flaw allowed an application to bypass these restrictions, thereby gaining unauthorized access to protected user data. The vulnerability does not require elevated privileges (PR:N) but does require user interaction (UI:R), meaning an attacker must trick a user into running or interacting with a malicious app. The attack vector is local (AV:L), indicating that the attacker must have local access to the device. The vulnerability impacts confidentiality (C:H) but does not affect integrity or availability. The weakness is classified under CWE-347, which relates to improper verification of cryptographic signatures or code-signing, leading to potential downgrade attacks. Apple fixed this issue by adding stricter code-signing enforcement in macOS Sequoia 15.6, preventing apps from exploiting the downgrade to access protected data. No public exploits have been reported yet, but the vulnerability poses a risk especially in environments where users might install untrusted applications or be targeted by social engineering.

The primary impact of CVE-2025-43185 is unauthorized disclosure of protected user data on affected macOS systems. This could lead to privacy violations, leakage of sensitive personal or corporate information, and potential compliance issues for organizations handling regulated data. Since the vulnerability does not affect data integrity or system availability, it is less likely to cause system disruption or data manipulation. However, the ability for an app to bypass code-signing restrictions and access protected data could facilitate further attacks, such as targeted espionage or credential theft. The requirement for local access and user interaction reduces the risk of widespread remote exploitation but still presents a significant threat in environments where users may run untrusted software or be subject to phishing or social engineering. Organizations with macOS endpoints, especially those in sectors like finance, healthcare, and government, could face increased risk of data breaches if not patched promptly.

To mitigate CVE-2025-43185, organizations should immediately update all macOS devices to version Sequoia 15.6 or later, where the vulnerability is fixed. Beyond patching, enforce strict application whitelisting and restrict installation of software from untrusted sources to reduce the risk of malicious apps exploiting this flaw. Implement endpoint protection solutions capable of detecting suspicious local app behavior and code-signing anomalies. Educate users about the risks of running unverified applications and the importance of avoiding social engineering traps that could lead to exploitation. Employ macOS security features such as System Integrity Protection (SIP) and Gatekeeper with strict settings to enhance code-signing enforcement. Regularly audit installed applications and monitor for unusual access to protected user data. For high-security environments, consider deploying device management policies that limit local user privileges and application installation rights. Finally, maintain an incident response plan to quickly address any suspected exploitation attempts.