CVE-2025-43510: 
macOS vulnerability analysis and mitigation

CVE-2025-43510 is a kernel-level memory corruption vulnerability in multiple Apple operating systems, classified as an improper locking flaw (CWE-667). A malicious application can exploit improper lock state checking to cause unexpected changes in memory shared between processes. The vulnerability affects iOS and iPadOS prior to 18.7.2, macOS Sonoma prior to 14.8.2, macOS Sequoia prior to 15.7.2, and pre-release versions of iOS 26, iPadOS 26, macOS Tahoe 26, tvOS 26, visionOS 26, and watchOS 26. Apple disclosed the vulnerability on November 5, 2025, with CVE assignment published December 12, 2025. It carries a CVSS v3.1 base score of 7.8 (High) (Apple Advisory iOS 18.7.2, Apple Advisory iOS 26.1).

The root cause is improper synchronization (CWE-667 / CWE-362) in the Apple kernel's management of inter-process shared memory regions. Specifically, the kernel fails to correctly check lock state before allowing modifications to shared memory, creating a race condition window where a malicious application can corrupt or manipulate memory that is shared with other processes. Exploitation requires local access and user interaction (e.g., a user running a malicious app), but no special privileges are needed. The vulnerability was exploited as part of the multi-stage DarkSword iOS exploit chain, which chains six vulnerabilities — including three zero-days — to achieve full device takeover, with CVE-2025-43510 serving as a kernel memory manipulation primitive (Google GTIG, Apple Advisory iOS 26.1).

Successful exploitation allows a malicious application to cause unexpected and unauthorized changes to inter-process shared memory, leading to data corruption, information disclosure, and potential arbitrary code execution at the kernel level. The high confidentiality, integrity, and availability impact scores reflect that an attacker can read sensitive data from other processes, tamper with shared state, and destabilize the system. In real-world attacks, this vulnerability was leveraged by the GHOSTBLADE malware and the DarkSword exploit kit for credential theft, crypto wallet draining, and broader data exfiltration from iPhones (Google GTIG, Lookout).

1. Delivery via malicious website or app: The attacker lures the target to visit a compromised or malicious website (DarkSword uses pure JavaScript delivered through legitimate-looking sites) or installs a malicious application on the target's iPhone.
2. Browser-based initial exploitation: A WebKit vulnerability (e.g., CVE-2025-43529) in the DarkSword chain is triggered via crafted web content, achieving initial code execution in the browser renderer process.
3. Sandbox escape: Additional vulnerabilities in the chain are used to escape the WebKit sandbox and gain broader process-level access.
4. Kernel memory manipulation via CVE-2025-43510: The malicious application exploits the improper lock state checking in the kernel's shared memory management. By racing against legitimate lock acquisition, the attacker causes unauthorized writes to inter-process shared memory, corrupting kernel data structures or injecting malicious data.
5. Privilege escalation and persistence: The kernel memory corruption is used to escalate privileges, bypass security controls, and establish persistence on the device.
6. Data exfiltration: The GHOSTBLADE payload or similar infostealer collects credentials, crypto wallet keys, contacts, messages, and other sensitive data, exfiltrating it to attacker-controlled infrastructure (Google GTIG, BleepingComputer, Lookout).

• Network: Unexpected outbound connections from iOS/macOS devices to unknown or suspicious IP addresses or domains; traffic patterns consistent with data exfiltration (large outbound transfers to unfamiliar endpoints).
• Process/Behavior: Unusual application behavior including apps accessing memory or data outside their expected scope; unexpected system crashes or kernel panics on affected devices; apps requesting or accessing inter-process shared memory regions abnormally.
• File System: Presence of unknown or unsigned applications installed outside the App Store; unexpected files in application data directories consistent with infostealer staging.
• Logs: Kernel panic logs or crash reports referencing shared memory or locking subsystems; system logs showing abnormal inter-process communication patterns; diagnostic logs indicating memory corruption events.
• Device State: Device running iOS/iPadOS below 18.7.2 or macOS Sonoma below 14.8.2 / Sequoia below 15.7.2 that has been exposed to untrusted applications or websites; unexpected battery drain or background data usage consistent with persistent malware activity (Google GTIG, Lookout).

Apple has released patches addressing CVE-2025-43510 in the following versions: iOS 18.7.2 and iPadOS 18.7.2 (released November 5, 2025), iOS 26.1 and iPadOS 26.1, macOS Sonoma 14.8.2, macOS Sequoia 15.7.2, macOS Tahoe 26.1, tvOS 26.1, visionOS 26.1, and watchOS 26.1. CISA mandated that U.S. federal agencies apply these patches by April 3, 2026. Immediate update of all affected Apple devices is the primary remediation; additionally, users should avoid installing applications from untrusted sources, remove any suspicious or unknown applications, and enable automatic updates. No configuration-based workaround is available as a substitute for patching (Apple Advisory iOS 18.7.2, CISA KEV, BleepingComputer CISA).

Google's Threat Intelligence Group (GTIG) published a detailed technical report on the DarkSword exploit chain in March 2026, attributing its use to both state-sponsored actors and commercial spyware vendors, and noting adoption by multiple threat actor groups including TA446 targeting Ukraine (Google GTIG). Lookout published independent threat intelligence confirming DarkSword's use of CVE-2025-43510 alongside WebKit and kernel vulnerabilities (Lookout). SentinelOne highlighted the GHOSTBLADE malware's weaponization of this vulnerability for credential theft. BleepingComputer, The Hacker News, The Register, and Tom's Guide all covered the story extensively, with Tom's Guide noting over 220 million iPhones potentially at risk. The security community reacted with urgency given the exploit chain's sophistication, its adoption by multiple threat actors, and the subsequent GitHub leak of the exploit code, which prompted Apple to expand iOS 18 security updates to additional older iPhone models (BleepingComputer, Malware News).