Apple on Monday shipped out-of-band security patches to address two zero-day vulnerabilities in iOS 12.5.3 that it says are being actively exploited in the wild.

The latest update, iOS 12.5.4, comes with three security fixes, including a memory corruption issue in the ASN.1 decoder (CVE-2021-30737) and two flaws concerning the WebKit browser engine that could be abused to achieve remote code execution —

• CVE-2021-30761 - A memory corruption issue that could be exploited to gain arbitrary code execution when processing maliciously crafted web content. The flaw was addressed with improved state management.
• CVE-2021-30762 - A use-after-free issue that could be exploited to gain arbitrary code execution when processing maliciously crafted web content. The flaw was resolved with improved memory management.

Both CVE-2021-30761 and CVE-2021-30762 were reported to Apple anonymously, with the Cupertino-based company stating in its advisory that it's aware of reports that the vulnerabilities "may have been actively exploited." As is usually the case, Apple didn't share any specifics on the nature of the attacks, the victims that may have been targeted, or the threat actors that may be abusing them.

One thing evident, however, is that the active exploitation attempts were directed against owners of older devices such as iPhone 5s, iPhone 6, iPhone 6 Plus, iPad Air, iPad mini 2, iPad mini 3, and iPod touch (6th generation). The move mirrors a similar fix that Apple rolled out on May 3 to remediate a buffer overflow vulnerability (CVE-2021-30666) in WebKit targeting the same set of devices.

Along with the two aforementioned flaws, Apple has patched a total of 12 zero-days affecting iOS, iPadOS, macOS, tvOS, and watchOS since the start of the year —

• CVE-2021-1782 (Kernel) - A malicious application may be able to elevate privileges
• CVE-2021-1870 (WebKit) - A remote attacker may be able to cause arbitrary code execution
• CVE-2021-1871 (WebKit) - A remote attacker may be able to cause arbitrary code execution
• CVE-2021-1879 (WebKit) - Processing maliciously crafted web content may lead to universal cross-site scripting
• CVE-2021-30657 (System Preferences) - A malicious application may bypass Gatekeeper checks
• CVE-2021-30661 (WebKit Storage)- Processing maliciously crafted web content may lead to arbitrary code execution
• CVE-2021-30663 (WebKit) - Processing maliciously crafted web content may lead to arbitrary code execution
• CVE-2021-30665 (WebKit) - Processing maliciously crafted web content may lead to arbitrary code execution
• CVE-2021-30666 (WebKit) - Processing maliciously crafted web content may lead to arbitrary code execution
• CVE-2021-30713 (TCC framework) - A malicious application may be able to bypass Privacy preferences

Users of Apple devices are recommended to update to the latest versions to mitigate the risk associated with the vulnerabilities.