Qualcomm and Samsung patched critical baseband and firmware flaws in mobile chipsets

Qualcomm disclosed and patched several high-severity chipset vulnerabilities affecting Snapdragon, FastConnect, modem, automotive, and IoT products, including CVE-2025-27034, CVE-2025-21483, CVE-2025-21427, CVE-2025-27043, and CVE-2025-21450. The flaws span modem, video, RTP, and GPS/GNSS firmware and include remote code execution, memory corruption, buffer over-read, and man-in-the-middle risks. Reported attack paths include malformed PLMN roaming responses, crafted RTP and video-stream payloads, and unauthenticated interception of GNSS assistance data delivered over HTTP. Several issues require no user interaction and affect low-level firmware, raising the risk of bypassing operating system protections; one Qualcomm modem flaw, CVE-2025-27034, was reported as exploited in the wild. Qualcomm addressed the issues through July and September 2025 security updates, with exposure likely to persist where OEM firmware rollout lags.

Samsung also issued fixes for multiple Exynos baseband vulnerabilities, including CVE-2024-55568, CVE-2025-26781, CVE-2025-26782, and CVE-2025-54329, affecting smartphones, wearables, and modem products. The bugs include NULL pointer dereference, out-of-bounds operations in RLC AM packet handling, and a heap overflow in the NAS signaling layer that can be triggered by malformed LTE or 5G traffic, Mobility Management packets, or multi-payload NAS messages such as SMS. Successful exploitation can crash or hang the modem, reboot devices, or cut off cellular service, and some flaws may be reachable through rogue base stations or compromised network infrastructure before higher-layer authentication or encryption takes effect. Samsung shipped patches in its October and November 2025 security updates, continuing a pattern of baseband security issues previously highlighted in Exynos modem research.