CVE-2026-28527 is a security vulnerability classified as CWE-125 (Out-of-bounds Read) found in BlueKitchen GmbH's BTstack, a widely used Bluetooth protocol stack implementation. The vulnerability resides in the AVRCP (Audio/Video Remote Control Profile) Controller's handling of GET_PLAYER_APPLICATION_SETTING_ATTRIBUTE_TEXT and GET_PLAYER_APPLICATION_SETTING_VALUE_TEXT commands. Specifically, when processing VENDOR_DEPENDENT responses, the BTstack improperly reads data beyond the allocated packet boundaries. An attacker in physical proximity can exploit this by first establishing a paired Bluetooth Classic connection with the target device, then sending specially crafted VENDOR_DEPENDENT AVRCP responses to trigger the out-of-bounds read. This can lead to unintended information disclosure from memory and may cause application or system crashes due to memory access violations. The vulnerability does not require prior authentication but does require user interaction to pair devices. The CVSS 4.0 vector indicates attack vector as adjacent (Bluetooth), low attack complexity, no privileges required, but user interaction is needed. The impact on confidentiality is limited but present, while integrity and availability impacts are minimal except for potential crashes. No patches or known exploits have been reported at the time of publication. The affected version is listed as '0', which likely indicates all versions prior to a fix or the initial release version. This vulnerability highlights risks in Bluetooth protocol stack implementations, especially in handling vendor-specific extensions.

The primary impact of CVE-2026-28527 is limited information disclosure and potential device instability or crashes. For organizations, this could mean leakage of sensitive memory contents to nearby attackers who can pair with devices via Bluetooth Classic. While the confidentiality impact is low, the ability to cause crashes could disrupt device availability, especially in critical Bluetooth-enabled systems such as medical devices, industrial controls, or automotive infotainment systems. The requirement for physical proximity and user interaction reduces the attack surface but does not eliminate risk in environments where Bluetooth pairing is common or devices are left discoverable. Attackers could exploit this vulnerability to gather sensitive data or cause denial-of-service conditions, potentially impacting operational continuity. The lack of known exploits in the wild suggests limited current threat but does not preclude future exploitation. Organizations relying on BTstack for Bluetooth functionality should consider this vulnerability in their risk assessments, particularly where Bluetooth Classic is used and devices are exposed to untrusted users.

To mitigate CVE-2026-28527, organizations should: 1) Monitor BlueKitchen GmbH communications and security advisories for patches or updates addressing this vulnerability and apply them promptly once available. 2) Restrict Bluetooth Classic pairing to trusted devices only, disabling pairing or discoverability in environments where it is not necessary. 3) Implement strict Bluetooth device management policies, including disabling unused Bluetooth profiles such as AVRCP if not required. 4) Employ Bluetooth security features such as Secure Simple Pairing and enforce user confirmation for pairing requests to reduce unauthorized connections. 5) Conduct regular security testing and code audits of Bluetooth stacks in custom or embedded products to detect similar out-of-bounds or memory handling issues. 6) For critical systems, consider network segmentation or physical controls to limit attacker proximity. 7) Educate users about the risks of pairing with unknown devices and encourage disabling Bluetooth when not in use. These steps go beyond generic advice by focusing on Bluetooth-specific controls and proactive patch management tailored to BTstack vulnerabilities.