An out-of-bounds write condition was discovered in core system components of Apple operating systems. The flaw originates from insufficient bounds verification on memory writes, a classic memory corruption issue that can destabilize critical processes and cause unexpected system termination. The primary effect is a denial of service manifested as abrupt application or system crashes, compromising reliability and availability for legitimate users.

Apple devices running iOS or iPadOS versions prior to 26.7, and macOS releases older than Sequoia 15.8 or Tahoe 26.7, are vulnerable. The fix is delivered through the specified OS updates and applies to all affected Apple operating systems.

While no direct remote exploit is documented, the vulnerability can be triggered by a malicious or poorly coded application that invokes the vulnerable code path. The CVSS score of 5.5 indicates moderate severity, and the EPSS score of <1% suggests a very low probability of exploitation. The issue is not listed in the CISA KEV catalog, implying no widespread public exploitation has been documented yet. Nevertheless, any application capable of triggering the out‑of‑bounds write may cause system instability, representing a significant denial‑of‑service risk.