If the bug caused memory writes to certain kernel functions, the console could potentially be rendered unusable if those functions were accessed.
Autoboot, which had been broken since 3.03 OE, was reimplemented.
This was only a minor update, however, and therefore was not needed by everyone running the custom firmware. It offers all past features from other custom firmwares, such as all features (except Location Free Player) built into the official 3.30, functionality as well as 1.50 features, such as ISO/CSO loading and homebrew support. This release includes a fix to security bug that overwrites certain parts of the RAM and also reintroduces the auto-boot program feature. This release includes the same changes made in 3.30 OE-A' except it now uses the 3.40 firmware.
It fixed a bug that caused data to be written to random addresses in the PSP's RAM.
Custom firmwares used a subset of the commonly known 1.50 firmware to enable a newer custom firmware to run homebrew capabilities, while newer custom firmwares use a custom IPL to launch the firmware and patch it.
On firmwares with 1.50 kernel installed, less used features are removed in newer versions including "Location Free Player" and Korean fonts in order to gain flas0 space.
The firmware adds support for 1.50 homebrew in addition to loading official Sony EBOOTs, integrating an ISO/CSO loader launched from the XMB game menu, and a recovery menu accessible upon boot-up.
(Or accessible from the XMB in some firmwares) 1.50 Proof of Concept On July 15 2006, a limited 1.50 custom firmware (named a proof of concept) was released by Dark Ale X, allowing the execution of version 1.00 EBOOTs, access to a limited recovery mode, and ability to automatically load an application upon start. Today, there are more developed versions such as "Casual V3" and the SE/OE/M33 firmwares.
This is custom firmware which is used for many PSP hacks.
It contains the same features of 2.71 SE-C, but also includes all 3.02 features excluding the Location Free player and the Korean fonts.
New features added to this custom firmware include WMA and Flash Player enabling through the Recovery Menu and cracking the Digital Rights Management of the PSX emulator, allowing users to share PSX games to other PSP systems.
Epsilon Bios On July 23 2006, a custom firmware, Epsilon Bios, was released for use with the Undiluted Platinum modchip.
This firmware could only be used on PSPs with the modchip.