OnePlus update blocks downgrades and custom ROMs by blowing a fuse

Summary

📰 This page or section is about an ongoing event.Check again later for more coverage. The OnePlus ColorOS 16.0.3.501 Anti-Rollback Fuse Incident refers to the January 2026 deployment of firmware updates by OnePlus that introduced a hardware-level anti-rollback mechanism. This permanently preventing users from downgrading their devices or installing custom ROMs. The updates, which affected the OnePlus 13, OnePlus 15, & OnePlus Ace 5 series, blow irreversible electronic fuses in the device's Qualcomm processor. Any subsequent attempt to install older firmware results in a permanent "hard brick" - the device becomes unusable. This cannot be repaired through standard methods.[1] OnePlus has not issued any official statement addressing the mechanism.[2] OnePlus was founded on December 16, 2013, by Pete Lau and Carl Pei, both former OPPO executives, with OPPO Electronics as the primary investor.[3] The company's first device, the OnePlus One, shipped with CyanogenMod, a commercial variant of the popular custom ROM, through an exclusive licensing agreement with Cyanogen Inc.[4] This partnership positioned OnePlus as a choice for modding enthusiasts. When that partnership collapsed due to Cyanogen's exclusivity deal with Micromax in India, OnePlus developed OxygenOS for global markets and HydrogenOS for China.[3] In July 2021, OnePlus merged OxygenOS with OPPO's ColorOS, sharing a common codebase while maintaining separate branding for different regions.[3] On January 18, 2026, users who updated to ColorOS 16.0.3.501 began reporting that their devices could not be reverted to previous versions. One OnePlus 13 owner reported that after flashing ColorOS 15, the phone entered EDL mode and was detected as "Qualcomm HS-USB QDLoader 9008," with the Chimera Rescue Tool unable to find a working programmer.[5] On January 19, 2026, XDA Forums member AdaUnlocked posted a warning thread documenting the issue with evidence including chat logs showing that the CPU anti-rollback fuse had ...