{"id":"CVE-2018-18397","details":"The userfaultfd implementation in the Linux kernel before 4.19.7 mishandles access control for certain UFFDIO_ ioctl calls, as demonstrated by allowing local users to write data into holes in a tmpfs file (if the user has read-only access to that file, and that file contains holes), related to fs/userfaultfd.c and mm/userfaultfd.c.","modified":"2026-04-16T06:15:17.380315084Z","published":"2018-12-12T10:29:00.240Z","related":["SUSE-SU-2019:0150-1","SUSE-SU-2019:0196-1","SUSE-SU-2019:0222-1","SUSE-SU-2019:0224-1","openSUSE-SU-2019:0065-1"],"references":[{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2019:0324"},{"type":"ADVISORY","url":"https://usn.ubuntu.com/3903-1/"},{"type":"ADVISORY","url":"https://usn.ubuntu.com/3903-2/"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHBA-2019:0327"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2019:0163"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2019:0831"},{"type":"ADVISORY","url":"https://usn.ubuntu.com/3901-1/"},{"type":"ADVISORY","url":"https://usn.ubuntu.com/3901-2/"},{"type":"ADVISORY","url":"https://access.redhat.com/errata/RHSA-2019:0202"},{"type":"REPORT","url":"https://bugs.chromium.org/p/project-zero/issues/detail?id=1700"},{"type":"FIX","url":"https://cdn.kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.14.87"},{"type":"FIX","url":"https://cdn.kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.19.7"},{"type":"FIX","url":"https://github.com/torvalds/linux/commit/29ec90660d68bbdd69507c1c8b4e33aa299278b1"},{"type":"FIX","url":"http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=29ec90660d68bbdd69507c1c8b4e33aa299278b1"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/torvalds/linux","events":[{"introduced":"0"},{"last_affected":"6e4664525b1db28f8c4e1130957f70a94c19213e"},{"introduced":"0"},{"last_affected":"39a8804455fb23f09157341d3ba7db6d7ae6ee76"},{"fixed":"29ec90660d68bbdd69507c1c8b4e33aa299278b1"}],"database_specific":{"versions":[{"introduced":"0"},{"last_affected":"3.11"},{"introduced":"0"},{"last_affected":"4.0"}]}}],"versions":["v2.6.12-rc2","v2.6.12-rc3","v2.6.12-rc4","v2.6.13","v2.6.13-rc1","v2.6.13-rc2","v2.6.13-rc3","v2.6.13-rc4","v2.6.13-rc5","v2.6.13-rc6","v2.6.13-rc7","v2.6.14-rc1","v2.6.14-rc2","v2.6.14-rc3","v2.6.15-rc1","v2.6.15-rc2","v2.6.15-rc4","v2.6.15-rc5","v2.6.15-rc7","v2.6.16","v2.6.16-rc1","v2.6.16-rc2","v2.6.16-rc3","v2.6.16-rc4","v2.6.16-rc5","v2.6.16-rc6","v2.6.17","v2.6.17-rc1","v2.6.17-rc2","v2.6.17-rc3","v2.6.17-rc4","v2.6.17-rc5","v2.6.17-rc6","v2.6.18","v2.6.18-rc1","v2.6.18-rc2","v2.6.18-rc3","v2.6.18-rc5","v2.6.18-rc6","v2.6.19-rc1","v2.6.19-rc2","v2.6.20-rc1","v2.6.20-rc2","v2.6.20-rc3","v2.6.20-rc4","v2.6.20-rc5","v2.6.20-rc6","v2.6.20-rc7","v2.6.21","v2.6.21-rc1","v2.6.21-rc2","v2.6.21-rc3","v2.6.21-rc4","v2.6.21-rc5","v2.6.21-rc6","v2.6.21-rc7","v2.6.22","v2.6.22-rc1","v2.6.22-rc2","v2.6.22-rc3","v2.6.22-rc4","v2.6.22-rc5","v2.6.22-rc6","v2.6.22-rc7","v2.6.23","v2.6.23-rc1","v2.6.23-rc2","v2.6.23-rc3","v2.6.23-rc4","v2.6.23-rc5","v2.6.23-rc6","v2.6.23-rc7","v2.6.23-rc8","v2.6.23-rc9","v2.6.24","v2.6.24-rc1","v2.6.24-rc2","v2.6.24-rc3","v2.6.24-rc4","v2.6.24-rc5","v2.6.24-rc6","v2.6.24-rc7","v2.6.24-rc8","v2.6.25","v2.6.25-rc1","v2.6.25-rc2","v2.6.25-rc3","v2.6.25-rc4","v2.6.25-rc5","v2.6.25-rc6","v2.6.25-rc7","v2.6.25-rc8","v2.6.25-rc9","v2.6.26","v2.6.26-rc1","v2.6.26-rc2","v2.6.26-rc3","v2.6.26-rc4","v2.6.26-rc5","v2.6.26-rc6","v2.6.26-rc7","v2.6.26-rc8","v2.6.26-rc9","v2.6.27","v2.6.27-rc1","v2.6.27-rc2","v2.6.27-rc3","v2.6.27-rc4","v2.6.27-rc5","v2.6.27-rc6","v2.6.27-rc7","v2.6.27-rc8","v2.6.27-rc9","v2.6.28","v2.6.28-rc1","v2.6.28-rc2","v2.6.28-rc3","v2.6.28-rc4","v2.6.28-rc5","v2.6.28-rc6","v2.6.28-rc7","v2.6.28-rc8","v2.6.28-rc9","v2.6.29","v2.6.29-rc1","v2.6.29-rc2","v2.6.29-rc3","v2.6.29-rc4","v2.6.29-rc5","v2.6.29-rc6","v2.6.29-rc7","v2.6.29-rc8","v2.6.30","v2.6.30-rc1","v2.6.30-rc2","v2.6.30-rc3","v2.6.30-rc4","v2.6.30-rc5","v2.6.30-rc6","v2.6.30-rc7","v2.6.30-rc8","v2.6.31","v2.6.31-rc1","v2.6.31-rc2","v2.6.31-rc3","v2.6.31-rc4","v2.6.31-rc5","v2.6.31-rc6","v2.6.31-rc7","v2.6.31-rc8","v2.6.31-rc9","v2.6.32","v2.6.32-rc1","v2.6.32-rc2","v2.6.32-rc3","v2.6.32-rc4","v2.6.32-rc5","v2.6.32-rc6","v2.6.32-rc7","v2.6.32-rc8","v2.6.33","v2.6.33-rc1","v2.6.33-rc2","v2.6.33-rc3","v2.6.33-rc4","v2.6.33-rc5","v2.6.33-rc6","v2.6.33-rc7","v2.6.33-rc8","v2.6.34","v2.6.34-rc1","v2.6.34-rc2","v2.6.34-rc3","v2.6.34-rc4","v2.6.34-rc5","v2.6.34-rc6","v2.6.34-rc7","v2.6.35","v2.6.35-rc1","v2.6.35-rc2","v2.6.35-rc3","v2.6.35-rc4","v2.6.35-rc5","v2.6.35-rc6","v2.6.36","v2.6.36-rc1","v2.6.36-rc2","v2.6.36-rc3","v2.6.36-rc4","v2.6.36-rc5","v2.6.36-rc6","v2.6.36-rc7","v2.6.36-rc8","v2.6.37","v2.6.37-rc1","v2.6.37-rc2","v2.6.37-rc3","v2.6.37-rc4","v2.6.37-rc5","v2.6.37-rc6","v2.6.37-rc7","v2.6.37-rc8","v2.6.38","v2.6.38-rc1","v2.6.38-rc2","v2.6.38-rc3","v2.6.38-rc4","v2.6.38-rc5","v2.6.38-rc6","v2.6.38-rc7","v2.6.38-rc8","v2.6.39","v2.6.39-rc1","v2.6.39-rc2","v2.6.39-rc3","v2.6.39-rc4","v2.6.39-rc5","v2.6.39-rc6","v2.6.39-rc7","v3.0","v3.0-rc1","v3.0-rc2","v3.0-rc3","v3.0-rc4","v3.0-rc5","v3.0-rc6","v3.0-rc7","v3.1","v3.1-rc1","v3.1-rc10","v3.1-rc2","v3.1-rc3","v3.1-rc4","v3.1-rc5","v3.1-rc6","v3.1-rc7","v3.1-rc8","v3.1-rc9","v3.10","v3.10-rc1","v3.10-rc2","v3.10-rc3","v3.10-rc4","v3.10-rc5","v3.10-rc6","v3.10-rc7","v3.11","v3.11-rc1","v3.11-rc2","v3.11-rc3","v3.11-rc4","v3.11-rc5","v3.11-rc6","v3.11-rc7","v3.12","v3.12-rc1","v3.12-rc2","v3.12-rc3","v3.12-rc4","v3.12-rc5","v3.12-rc6","v3.12-rc7","v3.13","v3.13-rc1","v3.13-rc2","v3.13-rc3","v3.13-rc4","v3.13-rc5","v3.13-rc6","v3.13-rc7","v3.13-rc8","v3.14","v3.14-rc1","v3.14-rc2","v3.14-rc3","v3.14-rc4","v3.14-rc5","v3.14-rc6","v3.14-rc7","v3.14-rc8","v3.15","v3.15-rc1","v3.15-rc2","v3.15-rc3","v3.15-rc4","v3.15-rc5","v3.15-rc6","v3.15-rc7","v3.15-rc8","v3.16","v3.16-rc1","v3.16-rc2","v3.16-rc3","v3.16-rc4","v3.16-rc5","v3.16-rc6","v3.16-rc7","v3.17","v3.17-rc1","v3.17-rc2","v3.17-rc3","v3.17-rc4","v3.17-rc5","v3.17-rc6","v3.17-rc7","v3.18","v3.18-rc1","v3.18-rc2","v3.18-rc3","v3.18-rc4","v3.18-rc5","v3.18-rc6","v3.18-rc7","v3.19","v3.19-rc1","v3.19-rc2","v3.19-rc3","v3.19-rc4","v3.19-rc5","v3.19-rc6","v3.19-rc7","v3.2","v3.2-rc1","v3.2-rc2","v3.2-rc3","v3.2-rc4","v3.2-rc5","v3.2-rc6","v3.2-rc7","v3.3","v3.3-rc1","v3.3-rc2","v3.3-rc3","v3.3-rc4","v3.3-rc5","v3.3-rc6","v3.3-rc7","v3.4","v3.4-rc1","v3.4-rc2","v3.4-rc3","v3.4-rc4","v3.4-rc5","v3.4-rc6","v3.4-rc7","v3.5","v3.5-rc1","v3.5-rc2","v3.5-rc3","v3.5-rc4","v3.5-rc5","v3.5-rc6","v3.5-rc7","v3.6","v3.6-rc1","v3.6-rc2","v3.6-rc3","v3.6-rc4","v3.6-rc5","v3.6-rc6","v3.6-rc7","v3.7","v3.7-rc1","v3.7-rc2","v3.7-rc3","v3.7-rc4","v3.7-rc5","v3.7-rc6","v3.7-rc7","v3.7-rc8","v3.8","v3.8-rc1","v3.8-rc2","v3.8-rc3","v3.8-rc4","v3.8-rc5","v3.8-rc6","v3.8-rc7","v3.9","v3.9-rc1","v3.9-rc2","v3.9-rc3","v3.9-rc4","v3.9-rc5","v3.9-rc6","v3.9-rc7","v3.9-rc8","v4.0","v4.0-rc1","v4.0-rc2","v4.0-rc3","v4.0-rc4","v4.0-rc5","v4.0-rc6","v4.0-rc7","v4.1","v4.1-rc1","v4.1-rc2","v4.1-rc3","v4.1-rc4","v4.1-rc5","v4.1-rc6","v4.1-rc7","v4.1-rc8","v4.10","v4.10-rc1","v4.10-rc2","v4.10-rc3","v4.10-rc4","v4.10-rc5","v4.10-rc6","v4.10-rc7","v4.10-rc8","v4.11","v4.11-rc1","v4.11-rc2","v4.11-rc3","v4.11-rc4","v4.11-rc5","v4.11-rc6","v4.11-rc7","v4.11-rc8","v4.12","v4.12-rc1","v4.12-rc2","v4.12-rc3","v4.12-rc4","v4.12-rc5","v4.12-rc6","v4.12-rc7","v4.13","v4.13-rc1","v4.13-rc2","v4.13-rc3","v4.13-rc4","v4.13-rc5","v4.13-rc6","v4.13-rc7","v4.14","v4.14-rc1","v4.14-rc2","v4.14-rc3","v4.14-rc4","v4.14-rc5","v4.14-rc6","v4.14-rc7","v4.14-rc8","v4.15","v4.15-rc1","v4.15-rc2","v4.15-rc3","v4.15-rc4","v4.15-rc5","v4.15-rc6","v4.15-rc7","v4.15-rc8","v4.15-rc9","v4.16","v4.16-rc1","v4.16-rc2","v4.16-rc3","v4.16-rc4","v4.16-rc5","v4.16-rc6","v4.16-rc7","v4.17","v4.17-rc1","v4.17-rc2","v4.17-rc3","v4.17-rc4","v4.17-rc5","v4.17-rc6","v4.17-rc7","v4.18","v4.18-rc1","v4.18-rc2","v4.18-rc3","v4.18-rc4","v4.18-rc5","v4.18-rc6","v4.18-rc7","v4.18-rc8","v4.19","v4.19-rc1","v4.19-rc2","v4.19-rc3","v4.19-rc4","v4.19-rc5","v4.19-rc6","v4.19-rc7","v4.19-rc8","v4.2","v4.2-rc1","v4.2-rc2","v4.2-rc3","v4.2-rc4","v4.2-rc5","v4.2-rc6","v4.2-rc7","v4.2-rc8","v4.20-rc1","v4.20-rc2","v4.20-rc3","v4.20-rc4","v4.3","v4.3-rc1","v4.3-rc2","v4.3-rc3","v4.3-rc4","v4.3-rc5","v4.3-rc6","v4.3-rc7","v4.4","v4.4-rc1","v4.4-rc2","v4.4-rc3","v4.4-rc4","v4.4-rc5","v4.4-rc6","v4.4-rc7","v4.4-rc8","v4.5","v4.5-rc1","v4.5-rc2","v4.5-rc3","v4.5-rc4","v4.5-rc5","v4.5-rc6","v4.5-rc7","v4.6","v4.6-rc1","v4.6-rc2","v4.6-rc3","v4.6-rc4","v4.6-rc5","v4.6-rc6","v4.6-rc7","v4.7","v4.7-rc1","v4.7-rc2","v4.7-rc3","v4.7-rc4","v4.7-rc5","v4.7-rc6","v4.7-rc7","v4.8","v4.8-rc1","v4.8-rc2","v4.8-rc3","v4.8-rc4","v4.8-rc5","v4.8-rc6","v4.8-rc7","v4.8-rc8","v4.9","v4.9-rc1","v4.9-rc2","v4.9-rc3","v4.9-rc4","v4.9-rc5","v4.9-rc6","v4.9-rc7","v4.9-rc8"],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2018-18397.json","vanir_signatures":[{"digest":{"function_hash":"88822189313798355102722030246757077988","length":2178},"signature_version":"v1","deprecated":false,"target":{"function":"userfaultfd_unregister","file":"fs/userfaultfd.c"},"id":"CVE-2018-18397-0f994766","source":"https://github.com/torvalds/linux/commit/29ec90660d68bbdd69507c1c8b4e33aa299278b1","signature_type":"Function"},{"source":"https://github.com/torvalds/linux/commit/29ec90660d68bbdd69507c1c8b4e33aa299278b1","signature_version":"v1","deprecated":false,"target":{"file":"fs/userfaultfd.c"},"id":"CVE-2018-18397-10186e0a","digest":{"threshold":0.9,"line_hashes":["162763651857891705297717051795681962885","252886811934717339831078341487762939236","309805251415622960061177283775140301717","38847988686236636808908195942635881069","239854422739929484586997821715980872123","192962523585601004029321267872298412274","252806154454766244371327930100815898920","117357893420595824141081426765656061905","182710314962732340766345304664397005824","110967525714789064919255637665598158688","87904863880200892183498761749370351284","188989513460040381571584380794163000761"]},"signature_type":"Line"},{"source":"https://github.com/torvalds/linux/commit/29ec90660d68bbdd69507c1c8b4e33aa299278b1","signature_version":"v1","deprecated":false,"target":{"file":"mm/userfaultfd.c"},"id":"CVE-2018-18397-11370444","digest":{"threshold":0.9,"line_hashes":["334349027950764353071431832243752082976","239525020285109700583892111967342200383","221755018383466999176800762684677061539","153318425643414298483846319986554345928","330318047361916487695601363781744480881","221755018383466999176800762684677061539"]},"signature_type":"Line"},{"source":"https://github.com/torvalds/linux/commit/29ec90660d68bbdd69507c1c8b4e33aa299278b1","signature_version":"v1","deprecated":false,"digest":{"function_hash":"226235449708140356725540298025928833845","length":3037},"id":"CVE-2018-18397-623cf3a0","target":{"function":"userfaultfd_register","file":"fs/userfaultfd.c"},"signature_type":"Function"}],"vanir_signatures_modified":"2026-04-11T11:40:02Z","unresolved_ranges":[{"events":[{"introduced":"0"},{"fixed":"4.19.7"}]},{"events":[{"introduced":"0"},{"last_affected":"7.0"}]},{"events":[{"introduced":"0"},{"last_affected":"7.0"}]},{"events":[{"introduced":"0"},{"last_affected":"7.4"}]},{"events":[{"introduced":"0"},{"last_affected":"7.6"}]},{"events":[{"introduced":"0"},{"last_affected":"7.4"}]},{"events":[{"introduced":"0"},{"last_affected":"7.5"}]},{"events":[{"introduced":"0"},{"last_affected":"7.6"}]},{"events":[{"introduced":"0"},{"last_affected":"7.4"}]},{"events":[{"introduced":"0"},{"last_affected":"7.6"}]},{"events":[{"introduced":"0"},{"last_affected":"7.0"}]},{"events":[{"introduced":"0"},{"last_affected":"14.04"}]},{"events":[{"introduced":"0"},{"last_affected":"16.04"}]},{"events":[{"introduced":"0"},{"last_affected":"18.04"}]},{"events":[{"introduced":"0"},{"last_affected":"18.10"}]}]}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V3","score":"CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N"}]}