{"cve":"CVE-2021-47641","nvd":{"published":"2025-02-26T06:37:05.883","modified":"2026-06-17T04:18:13.427","status":"Modified","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nvideo: fbdev: cirrusfb: check pixclock to avoid divide by zero\n\nDo a sanity check on pixclock value to avoid divide by zero.\n\nIf the pixclock value is zero, the cirrusfb driver will round up\npixclock to get the derived frequency as close to maxclock as\npossible.\n\nSyzkaller reported a divide error in cirrusfb_check_pixclock.\n\ndivide error: 0000 [#1] SMP KASAN PTI\nCPU: 0 PID: 14938 Comm: cirrusfb_test Not tainted 5.15.0-rc6 #1\nHardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.11.0-2\nRIP: 0010:cirrusfb_check_var+0x6f1/0x1260\n\nCall Trace:\n fb_set_var+0x398/0xf90\n do_fb_ioctl+0x4b8/0x6f0\n fb_ioctl+0xeb/0x130\n __x64_sys_ioctl+0x19d/0x220\n do_syscall_64+0x3a/0x80\n entry_SYSCALL_64_after_hwframe+0x44/0xae","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","score":5.5},"cwes":["CWE-369"],"references":["https://git.kernel.org/stable/c/1d3fb46439ad4e8f0c5739eb33d1875ac9e0f135","https://git.kernel.org/stable/c/40b13e3d85744210db13457785646634e2d056bd","https://git.kernel.org/stable/c/45800c42ef000f417270bcfc08630e42486fca99","https://git.kernel.org/stable/c/53a2088a396cfa1da92690a1da289634cd73bf0d","https://git.kernel.org/stable/c/5c6f402bdcf9e7239c6bc7087eda71ac99b31379"],"products":["linux:linux_kernel"],"source":"nvd","synced_at":"2026-10-19T21:59:48.811064707+00:00"},"epss":{"cve":"CVE-2021-47641","score":0.00253,"percentile":0.16823,"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."]}