{"id":"DEBIAN-CVE-2024-50048","details":"In the Linux kernel, the following vulnerability has been resolved:  fbcon: Fix a NULL pointer dereference issue in fbcon_putcs  syzbot has found a NULL pointer dereference bug in fbcon. Here is the simplified C reproducer:  struct param { \tuint8_t type; \tstruct tiocl_selection ts; };  int main() { \tstruct fb_con2fbmap con2fb; \tstruct param param;  \tint fd = open(\"/dev/fb1\", 0, 0);  \tcon2fb.console = 0x19; \tcon2fb.framebuffer = 0; \tioctl(fd, FBIOPUT_CON2FBMAP, &con2fb);  \tparam.type = 2; \tparam.ts.xs = 0; param.ts.ys = 0; \tparam.ts.xe = 0; param.ts.ye = 0; \tparam.ts.sel_mode = 0;  \tint fd1 = open(\"/dev/tty1\", O_RDWR, 0); \tioctl(fd1, TIOCLINUX, &param);  \tcon2fb.console = 1; \tcon2fb.framebuffer = 0; \tioctl(fd, FBIOPUT_CON2FBMAP, &con2fb);  \treturn 0; }  After calling ioctl(fd1, TIOCLINUX, &param), the subsequent ioctl(fd, FBIOPUT_CON2FBMAP, &con2fb) causes the kernel to follow a different execution path:   set_con2fb_map   -\u003e con2fb_init_display    -\u003e fbcon_set_disp     -\u003e redraw_screen      -\u003e hide_cursor       -\u003e clear_selection        -\u003e highlight         -\u003e invert_screen          -\u003e do_update_region           -\u003e fbcon_putcs            -\u003e ops-\u003eputcs  Since ops-\u003eputcs is a NULL pointer, this leads to a kernel panic. To prevent this, we need to call set_blitting_type() within set_con2fb_map() to properly initialize ops-\u003eputcs.","modified":"2026-09-15T09:03:12.561619341Z","published":"2024-10-21T20:15:17.580Z","upstream":["CVE-2024-50048"],"references":[{"type":"ADVISORY","url":"https://security-tracker.debian.org/tracker/CVE-2024-50048"}],"affected":[{"package":{"name":"linux","ecosystem":"Debian:12","purl":"pkg:deb/debian/linux?arch=source&distro=bookworm"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"6.1.115-1"}]}],"versions":["6.1.106-1","6.1.106-2","6.1.106-3","6.1.112-1","6.1.27-1","6.1.37-1","6.1.38-1","6.1.38-2","6.1.38-2~bpo11+1","6.1.38-3","6.1.38-4","6.1.38-4~bpo11+1","6.1.52-1","6.1.55-1","6.1.55-1~bpo11+1","6.1.64-1","6.1.66-1","6.1.67-1","6.1.69-1","6.1.69-1~bpo11+1","6.1.76-1","6.1.76-1~bpo11+1","6.1.82-1","6.1.85-1","6.1.90-1","6.1.90-1~bpo11+1","6.1.94-1","6.1.94-1~bpo11+1","6.1.98-1","6.1.99-1"],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2024-50048.json"}},{"package":{"name":"linux","ecosystem":"Debian:13","purl":"pkg:deb/debian/linux?arch=source&distro=trixie"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"6.11.4-1"}]}],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2024-50048.json"}},{"package":{"name":"linux","ecosystem":"Debian:14","purl":"pkg:deb/debian/linux?arch=source&distro=forky"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"6.11.4-1"}]}],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2024-50048.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H"}]}