{"cve":"CVE-2021-47383","nvd":{"published":"2024-05-21T15:15:23.873","modified":"2026-08-04T10:17:00.893","status":"Modified","description":"In the Linux kernel, the following vulnerability has been resolved:\n\ntty: Fix out-of-bound vmalloc access in imageblit\n\nThis issue happens when a userspace program does an ioctl\nFBIOPUT_VSCREENINFO passing the fb_var_screeninfo struct\ncontaining only the fields xres, yres, and bits_per_pixel\nwith values.\n\nIf this struct is the same as the previous ioctl, the\nvc_resize() detects it and doesn't call the resize_screen(),\nleaving the fb_var_screeninfo incomplete. And this leads to\nthe updatescrollmode() calculates a wrong value to\nfbcon_display->vrows, which makes the real_y() return a\nwrong value of y, and that value, eventually, causes\nthe imageblit to access an out-of-bound address value.\n\nTo solve this issue I made the resize_screen() be called\neven if the screen does not need any resizing, so it will\n\"fix and fill\" the fb_var_screeninfo independently.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H","score":7.1},"cwes":["CWE-125"],"references":["https://git.kernel.org/stable/c/067c694d06040db6f0c65281bb358452ca6d85b9","https://git.kernel.org/stable/c/3b0c406124719b625b1aba431659f5cdc24a982c","https://git.kernel.org/stable/c/699d926585daa6ec44be556cdc1ab89e5d54557b","https://git.kernel.org/stable/c/70aed03b1d5a5df974f456cdc8eedb213c94bb8b","https://git.kernel.org/stable/c/7e71fcedfda6f7de18f850a6b36e78d78b04476f"],"products":["linux:linux_kernel"],"source":"nvd","synced_at":"2026-10-19T21:50:30.954589733+00:00"},"epss":{"cve":"CVE-2021-47383","score":0.00265,"percentile":0.18471,"date":"2026-10-31"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}