Samsung Galaxy S24/S25 Ultra battery drain, overheating after July 2026 patch
After Samsung released its July 2026 security patch (One UI 8.5), users of the flagship Galaxy S24 Ultra and Galaxy S25 Ultra have reported severe battery‑drain and excessive heat. Reports from forums and Reddit describe standby losses of 5‑7 % per hour, with some devices dropping from about 85 % to 5 % within a few hours of use. Temperatures have risen well above normal operating levels, with measurements up to 40 °C and isolated cases reaching 76 °C. A smaller number of users also note slower charging speeds.
The problem has been documented in many countries, including China, Iceland, Romania, Bulgaria, Egypt, Germany, Finland, Mexico and Portugal. Several investigations point to a possible software cause: an encrypted WhatsApp backup that remains active after the update, keeping the processor awake and draining power. Samsung has not officially confirmed the issue nor announced a fix, and users are advised to monitor battery usage, limit background apps and await a corrective update.
Entities: Galaxy S24 Ultra · Galaxy S25 Ultra · One UI 8.5 · Samsung Electronics Co Ltd · Samsung Electronics Co., Ltd. · Samsung Galaxy S24 Ultra · Samsung Galaxy S25 Ultra · WhatsApp · WhatsApp Messenger
Claims
What the coverage asserts, and how well corroborated each claim is across sources.
- [○ 1 SOURCE] The July patch addresses roughly 60 security vulnerabilities, including five classified as critical. (Samsung release information)
- [● 2 SOURCES] Some users reported battery levels dropping from about 85% to 5% within two hours of screen use. (user reports)
- [● 3 SOURCES] The likely cause is a stuck WhatsApp encrypted backup process that creates a wakelock, keeping the phone active. (user investigations)
- [● 3 SOURCES] The update also caused devices to overheat and resulted in slower charging. (user reports)
- [○ 1 SOURCE] The patch is being rolled out to 34 Samsung devices, among them the Galaxy S24 Ultra and S25 Ultra. (Samsung release information)
- [○ 1 SOURCE] In some cases, standby battery loss reached up to 24% per hour. (user reports)
- [● 3 SOURCES] The July 2026 security update for Galaxy S24 Ultra and S25 Ultra caused accelerated battery drain of 5‑7% per hour in standby. (user reports)
- [● 3 SOURCES] Samsung has not publicly confirmed the issue nor provided an official fix. (company statements)