{"cve":"CVE-2018-12633","nvd":{"published":"2018-06-22T00:29:00.270","modified":"2026-06-17T01:38:05.937","status":"Modified","description":"An issue was discovered in the Linux kernel through 4.17.2. vbg_misc_device_ioctl() in drivers/virt/vboxguest/vboxguest_linux.c reads the same user data twice with copy_from_user. The header part of the user data is double-fetched, and a malicious user thread can tamper with the critical variables (hdr.size_in and hdr.size_out) in the header between the two fetches because of a race condition, leading to severe kernel errors, such as buffer over-accesses. This bug can cause a local denial of service and information leakage.","cvss_v4":null,"cvss_v3":{"version":"3.0","vector":"CVSS:3.0/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:N/A:H","score":6.3},"cwes":["CWE-362"],"references":["http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=bd23a7269834dc7c1f93e83535d16ebc44b75eba","https://bugzilla.kernel.org/show_bug.cgi?id=200131","https://github.com/torvalds/linux/commit/bd23a7269834dc7c1f93e83535d16ebc44b75eba","http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=bd23a7269834dc7c1f93e83535d16ebc44b75eba","https://bugzilla.kernel.org/show_bug.cgi?id=200131"],"products":["linux:linux_kernel"],"source":"nvd","synced_at":"2026-10-19T20:51:47.459859389+00:00"},"epss":{"cve":"CVE-2018-12633","score":0.0026,"percentile":0.17817,"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."]}