Add kernelCTF CVE-2026-31419_cos

[n132]

Init the PR.

[koczkatamas]

Hey! kernelCTF rules ask you to use kernelXDK including getting the symbol addresses dynamically instead of hardcoding for a specific target. See this guide: https://xdk.dev/libxdk/sample_exploit.html

[n132]

Thanks for your review, KT! We'll solve this problem.

[n132]

@koczkatamas, libxdk is applied to the latest version, but we keep the ENTER_GADGET since it's a novel technique related to one.

    #define ENTER_GADGET                0xffffffff82536399  // enter 0xff48, 0x89; ret;

Please let us know if we need to modify to satisfy the requirements.

Thanks,
Xiang