The issue was addressed with improved memory handling. This issue is fixed in Safari 26.4, iOS 26.4 and iPadOS 26.4, macOS Tahoe 26.4, tvOS 26.4, visionOS 26.4, watchOS 26.4. A malicious website may be able to process restricted web content outside the sandbox.

A flaw was found in the FTP GVfs backend. A malicious FTP server can exploit this vulnerability by providing an arbitrary IP address and port in its passive mode (PASV) response. The client unconditionally trusts this information and attempts to connect to the specified endpoint, allowing the malicious server to probe for open ports accessible from the client's network.

A logic issue was addressed with improved state management. This issue is fixed in Safari 26.4, iOS 18.7.7 and iPadOS 18.7.7, iOS 26.4 and iPadOS 26.4, macOS Tahoe 26.4, visionOS 26.4. A malicious website may be able to access script message handlers intended for other origins.

A flaw was found in the FTP GVfs backend. A remote attacker could exploit this input validation vulnerability by supplying specially crafted file paths containing carriage return and line feed (CRLF) sequences. These unsanitized sequences allow the attacker to terminate intended FTP commands and inject arbitrary FTP commands, potentially leading to arbitrary code execution or other severe impacts.

A flaw was found in the GStreamer gst-plugins-bad package. When processing a malformed H.266/VVC video stream with a crafted aspect ratio indicator value, the H.266 parser performs an out-of-bounds read of up to 8 bytes from adjacent memory. This flaw allows an attacker to craft a malicious H.266 video file or stream that, when processed by a GStreamer-based application, could leak limited memory contents through video metadata, potentially exposing sensitive information from the application's address space.

A flaw was found in Keycloak, an open-source identity and access management solution. When a user account is temporarily locked due to repeated failed login attempts, an attacker with valid client credentials can exploit the Client-Initiated Backchannel Authentication (CIBA) flow to bypass this brute-force protection. This allows continued authentication attempts and token issuance even when the account should be locked, potentially enabling further unauthorized access attempts.