{"id":"CVE-2022-50511","title":"lib/fonts: fix undefined behavior in bit shift for get_default_font","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\nlib/fonts: fix undefined behavior in bit shift for get_default_font\n\nShifting signed 32-bit value by 31 bits is undefined, so changing\nsignificant bit to unsigned.  The…","severity":"none","vendor":"Linux","product":"Linux","affected":["Linux >= c81f717cb9e0bd91dc4b98753cb2705ab0fe2801 < e039929e36818507e90901edae87f6fa8bc81093","Linux >= c81f717cb9e0bd91dc4b98753cb2705ab0fe2801 < c9a9aa02f0fa3318e0ae5774f404419a1b4759ca","Linux >= c81f717cb9e0bd91dc4b98753cb2705ab0fe2801 < e83b47580a0738361772d6f24286adfdaba57e36","Linux >= c81f717cb9e0bd91dc4b98753cb2705ab0fe2801 < 9c14a85e18a58c102ec223144b7edb5b345c1bea","Linux >= c81f717cb9e0bd91dc4b98753cb2705ab0fe2801 < 890d91b31f4874361e0df047f57d268a7021cb12","Linux >= c81f717cb9e0bd91dc4b98753cb2705ab0fe2801 < 6fe888c4d2fb174408e4540bb2d5602b9f507f90","Linux 2.6.23"],"ssvc":{"exploitation":"none","automatable":"no","technicalImpact":"partial","timestamp":"2026-11-05T20:12:46.317948Z"},"published":"2025-10-07","updated":"2026-11-05","sourceUpdated":"2026-11-05T20:20:50.224Z","source":"CVEORG","sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2022-50511","references":[{"url":"https://git.kernel.org/stable/c/e039929e36818507e90901edae87f6fa8bc81093"},{"url":"https://git.kernel.org/stable/c/c9a9aa02f0fa3318e0ae5774f404419a1b4759ca"},{"url":"https://git.kernel.org/stable/c/e83b47580a0738361772d6f24286adfdaba57e36"},{"url":"https://git.kernel.org/stable/c/9c14a85e18a58c102ec223144b7edb5b345c1bea"},{"url":"https://git.kernel.org/stable/c/890d91b31f4874361e0df047f57d268a7021cb12"},{"url":"https://git.kernel.org/stable/c/6fe888c4d2fb174408e4540bb2d5602b9f507f90"}],"tags":["cve.org"],"epss":0.00161,"epssPercentile":0.05312,"ingestedAt":"2026-11-05T22:38:31.744Z","slug":"CVE-2022-50511","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\nlib/fonts: fix undefined behavior in bit shift for get_default_font\n\nShifting signed 32-bit value by 31 bits is undefined, so changing\nsignificant bit to unsigned.  The UBSAN warning calltrace like below:\n\nUBSAN: shift-out-of-bounds in lib/fonts/fonts.c:139:20\nleft shift of 1 by 31 places cannot be represented in type 'int'\n <TASK>\n dump_stack_lvl+0x7d/0xa5\n dump_stack+0x15/0x1b\n ubsan_epilogue+0xe/0x4e\n __ubsan_handle_shift_out_of_bounds+0x1e7/0x20c\n get_default_font+0x1c7/0x1f0\n fbcon_startup+0x347/0x3a0\n do_take_over_console+0xce/0x270\n do_fbcon_takeover+0xa1/0x170\n do_fb_registered+0x2a8/0x340\n fbcon_fb_registered+0x47/0xe0\n register_framebuffer+0x294/0x4a0\n __drm_fb_helper_initial_config_and_unlock+0x43c/0x880 [drm_kms_helper]\n drm_fb_helper_initial_config+0x52/0x80 [drm_kms_helper]\n drm_fbdev_client_hotplug+0x156/0x1b0 [drm_kms_helper]\n drm_fbdev_generic_setup+0xfc/0x290 [drm_kms_helper]\n bochs_pci_probe+0x6ca/0x772 [bochs]\n local_pci_probe+0x4d/0xb0\n pci_device_probe+0x119/0x320\n really_probe+0x181/0x550\n __driver_probe_device+0xc6/0x220\n driver_probe_device+0x32/0x100\n __driver_attach+0x195/0x200\n bus_for_each_dev+0xbb/0x120\n driver_attach+0x27/0x30\n bus_add_driver+0x22e/0x2f0\n driver_register+0xa9/0x190\n __pci_register_driver+0x90/0xa0\n bochs_pci_driver_init+0x52/0x1000 [bochs]\n do_one_initcall+0x76/0x430\n do_init_module+0x61/0x28a\n load_module+0x1f82/0x2e50\n __do_sys_finit_module+0xf8/0x190\n __x64_sys_finit_module+0x23/0x30\n do_syscall_64+0x58/0x80\n entry_SYSCALL_64_after_hwframe+0x63/0xcd\n </TASK>\n\n## Affected\n\n- `Linux >= c81f717cb9e0bd91dc4b98753cb2705ab0fe2801 < e039929e36818507e90901edae87f6fa8bc81093`\n- `Linux >= c81f717cb9e0bd91dc4b98753cb2705ab0fe2801 < c9a9aa02f0fa3318e0ae5774f404419a1b4759ca`\n- `Linux >= c81f717cb9e0bd91dc4b98753cb2705ab0fe2801 < e83b47580a0738361772d6f24286adfdaba57e36`\n- `Linux >= c81f717cb9e0bd91dc4b98753cb2705ab0fe2801 < 9c14a85e18a58c102ec223144b7edb5b345c1bea`\n- `Linux >= c81f717cb9e0bd91dc4b98753cb2705ab0fe2801 < 890d91b31f4874361e0df047f57d268a7021cb12`\n- `Linux >= c81f717cb9e0bd91dc4b98753cb2705ab0fe2801 < 6fe888c4d2fb174408e4540bb2d5602b9f507f90`\n- `Linux 2.6.23`\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"sunlit","depthScore":3,"depthScoreParts":{"impact":2.8,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}