{"schema_version":"1.7.5","id":"CVE-2025-39817","published":"2025-09-16T13:00:17.776Z","modified":"2026-07-15T01:49:10.871535423Z","related":["ALSA-2025:18281","ALSA-2025:18318","ALSA-2025:19102","ALSA-2025:19103","SUSE-SU-2026:0962-1","SUSE-SU-2026:1041-1","SUSE-SU-2026:1078-1","SUSE-SU-2026:1081-1","SUSE-SU-2026:20555-1","SUSE-SU-2026:20570-1","SUSE-SU-2026:20599-1","SUSE-SU-2026:20615-1","SUSE-SU-2026:21114-1","SUSE-SU-2026:21123-1","SUSE-SU-2026:21255-1","openSUSE-SU-2026:20287-1"],"summary":"efivarfs: Fix slab-out-of-bounds in efivarfs_d_compare","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nefivarfs: Fix slab-out-of-bounds in efivarfs_d_compare\n\nObserved on kernel 6.6 (present on master as well):\n\n  BUG: KASAN: slab-out-of-bounds in memcmp+0x98/0xd0\n  Call trace:\n   kasan_check_range+0xe8/0x190\n   __asan_loadN+0x1c/0x28\n   memcmp+0x98/0xd0\n   efivarfs_d_compare+0x68/0xd8\n   __d_lookup_rcu_op_compare+0x178/0x218\n   __d_lookup_rcu+0x1f8/0x228\n   d_alloc_parallel+0x150/0x648\n   lookup_open.isra.0+0x5f0/0x8d0\n   open_last_lookups+0x264/0x828\n   path_openat+0x130/0x3f8\n   do_filp_open+0x114/0x248\n   do_sys_openat2+0x340/0x3c0\n   __arm64_sys_openat+0x120/0x1a0\n\nIf dentry->d_name.len < EFI_VARIABLE_GUID_LEN , 'guid' can become\nnegative, leadings to oob. The issue can be triggered by parallel\nlookups using invalid filename:\n\n  T1\t\t\tT2\n  lookup_open\n   ->lookup\n    simple_lookup\n     d_add\n     // invalid dentry is added to hash list\n\n\t\t\tlookup_open\n\t\t\t d_alloc_parallel\n\t\t\t  __d_lookup_rcu\n\t\t\t   __d_lookup_rcu_op_compare\n\t\t\t    hlist_bl_for_each_entry_rcu\n\t\t\t    // invalid dentry can be retrieved\n\t\t\t     ->d_compare\n\t\t\t      efivarfs_d_compare\n\t\t\t      // oob\n\nFix it by checking 'guid' before cmp.","affected":[{"ranges":[{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"da27a24383b2b10bf6ebd0db29b325548aafecb4"},{"fixed":"0f63fbabeaaaaaaf5b742a2f4c1b4590d50bf1f6"},{"fixed":"794399019301944fd6d2e0d7a51b3327e26c410e"},{"fixed":"568e7761279b99c6daa3002290fd6d8047ddb6d2"},{"fixed":"d7f5e35e70507d10cbaff5f9e194ed54c4ee14f7"},{"fixed":"925599eba46045930b850a98ae594d2e3028ac40"},{"fixed":"c2925cd6207079c3f4d040d082515db78d63afbf"},{"fixed":"71581a82f38e5a4d807d71fc1bb59aead80ccf95"},{"fixed":"a6358f8cf64850f3f27857b8ed8c1b08cfc4685c"}]},{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"0"},{"last_affected":"688289c4b745c018b3449b4b4c5a2030083c8eaf"}]},{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"3.8.2"},{"fixed":"3.9"}]}],"versions":["v3.8","v3.8.1","v3.8-rc7","v3.8-rc6","v3.8-rc5","v3.8-rc2","v3.8-rc1","v3.8-rc3","v3.8-rc4","v3.7","v3.7-rc1","v3.6","v3.7-rc6","v3.7-rc7","v3.7-rc3","v3.7-rc8","v3.7-rc2","v3.7-rc4","v3.7-rc5","v3.6-rc7","v3.6-rc1","v3.5-rc3","v3.6-rc6","v3.6-rc5","v3.5","v3.6-rc3","v3.6-rc4","v3.6-rc2","v3.4-rc4","v3.5-rc7","v3.5-rc5","v3.5-rc6","v3.5-rc2","v3.5-rc1","v3.5-rc4","v3.4","v3.4-rc2","v3.4-rc1","v3.4-rc7","v3.4-rc6","v3.4-rc3","v3.4-rc5","v3.3","v3.3-rc6","v3.3-rc3","v3.3-rc7","v3.3-rc2","v3.3-rc5","v3.2","v3.3-rc4","v3.3-rc1","v3.2-rc4","v3.2-rc7","v3.2-rc6","v3.2-rc5","v3.2-rc3","v3.1","v3.2-rc2","v3.2-rc1","v3.1-rc1","v3.1-rc9","v3.1-rc8","v3.1-rc10","v3.1-rc7","v3.1-rc3","v3.1-rc2","v3.1-rc4","v3.1-rc5","v3.0","v3.1-rc6","v3.0-rc7","v3.0-rc4","v3.0-rc6","v3.0-rc5","v3.0-rc3","v3.0-rc1","v2.6.39","v3.0-rc2","v2.6.38","v2.6.39-rc2","v2.6.39-rc7","v2.6.39-rc5","v2.6.39-rc1","v2.6.38-rc7","v2.6.39-rc6","v2.6.39-rc4","v2.6.39-rc3","v2.6.37","v2.6.38-rc1","v2.6.38-rc8","v2.6.38-rc2","v2.6.38-rc6","v2.6.38-rc5","v2.6.38-rc4","v2.6.38-rc3","v2.6.37-rc4","v2.6.37-rc2","v2.6.36","v2.6.37-rc5","v2.6.37-rc8","v2.6.37-rc7","v2.6.37-rc6","v2.6.37-rc1","v2.6.37-rc3","v2.6.36-rc6","v2.6.35-rc4","v2.6.36-rc8","v2.6.35","v2.6.36-rc7","v2.6.36-rc3","v2.6.36-rc5","v2.6.36-rc4","v2.6.36-rc2","v2.6.36-rc1","v2.6.35-rc5","v2.6.35-rc6","v2.6.34","v2.6.35-rc3","v2.6.35-rc1","v2.6.35-rc2","v2.6.34-rc7","v2.6.34-rc6","v2.6.34-rc5","v2.6.34-rc4","v2.6.34-rc3","v2.6.34-rc2","v2.6.34-rc1","v2.6.33","v2.6.33-rc6","v2.6.33-rc8","v2.6.33-rc4","v2.6.33-rc5","v2.6.33-rc3","v2.6.33-rc7","v2.6.33-rc2","v2.6.32","v2.6.33-rc1","v2.6.32-rc8","v2.6.32-rc7","v2.6.32-rc6","v2.6.31","v2.6.32-rc5","v2.6.32-rc4","v2.6.32-rc2","v2.6.32-rc1","v2.6.32-rc3","v2.6.31-rc9","v2.6.31-rc1","v2.6.31-rc7","v2.6.31-rc8","v2.6.31-rc6","v2.6.30-rc6","v2.6.30","v2.6.31-rc4","v2.6.31-rc5","v2.6.31-rc3","v2.6.31-rc2","v2.6.30-rc7","v2.6.30-rc8","v2.6.30-rc5","v2.6.30-rc3","v2.6.30-rc4","v2.6.30-rc1","v2.6.30-rc2","v2.6.29","v2.6.29-rc8","v2.6.29-rc7","v2.6.29-rc5","v2.6.29-rc1","v2.6.29-rc6","v2.6.29-rc4","v2.6.29-rc3","v2.6.29-rc2","v2.6.28","v2.6.28-rc7","v2.6.28-rc9","v2.6.28-rc8","v2.6.28-rc6","v2.6.28-rc5","v2.6.28-rc4","v2.6.28-rc2","v2.6.28-rc3","v2.6.28-rc1","v2.6.27","v2.6.27-rc7","v2.6.27-rc9","v2.6.27-rc8","v2.6.27-rc5","v2.6.27-rc6","v2.6.27-rc4","v2.6.27-rc1","v2.6.27-rc3","v2.6.27-rc2","v2.6.26","v2.6.26-rc9","v2.6.26-rc8","v2.6.26-rc3","v2.6.26-rc7","v2.6.26-rc6","v2.6.26-rc5","v2.6.26-rc4","v2.6.26-rc2","v2.6.26-rc1","v2.6.25","v2.6.25-rc7","v2.6.25-rc9","v2.6.25-rc8","v2.6.25-rc6","v2.6.25-rc5","v2.6.25-rc3","v2.6.25-rc4","v2.6.24","v2.6.25-rc2","v2.6.25-rc1","v2.6.24-rc8","v2.6.24-rc7","v2.6.24-rc6","v2.6.24-rc5","v2.6.24-rc4","v2.6.24-rc3","v2.6.24-rc2","v2.6.24-rc1","v2.6.23","v2.6.23-rc9","v2.6.23-rc8","v2.6.23-rc5","v2.6.23-rc7","v2.6.23-rc6","v2.6.23-rc4","v2.6.23-rc3","v2.6.23-rc2","v2.6.23-rc1","v2.6.22","v2.6.22-rc7","v2.6.22-rc6","v2.6.22-rc5","v2.6.22-rc4","v2.6.22-rc3","v2.6.22-rc2","v2.6.22-rc1","v2.6.21","v2.6.21-rc7","v2.6.21-rc6","v2.6.21-rc5","v2.6.21-rc4","v2.6.21-rc3","v2.6.21-rc2","v2.6.21-rc1","v2.6.20-rc7","v2.6.20-rc6","v2.6.20-rc5","v2.6.20-rc4","v2.6.20-rc3","v2.6.20-rc1","v2.6.20-rc2","v2.6.19-rc2","v2.6.18","v2.6.19-rc1","v2.6.18-rc6","v2.6.18-rc5","v2.6.18-rc3","v2.6.18-rc2","v2.6.18-rc1","v2.6.17","v2.6.17-rc4","v2.6.17-rc6","v2.6.17-rc5","v2.6.17-rc3","v2.6.17-rc2","v2.6.17-rc1","v2.6.16","v2.6.16-rc6","v2.6.16-rc4","v2.6.16-rc5","v2.6.16-rc3","v2.6.16-rc2","v2.6.16-rc1","v2.6.15-rc7","v2.6.15-rc5","v2.6.15-rc4","v2.6.15-rc2","v2.6.15-rc1","v2.6.14-rc3","v2.6.14-rc2","v2.6.14-rc1","v2.6.13","v2.6.13-rc7","v2.6.13-rc6","v2.6.13-rc5","v2.6.13-rc3","v2.6.13-rc4","v2.6.13-rc2","v2.6.13-rc1","v2.6.12-rc4","v2.6.12-rc3","v2.6.12-rc2"],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2025-39817.json"}},{"package":{"name":"Kernel","ecosystem":"Linux"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"3.9.0"},{"fixed":"5.4.298"}]},{"type":"ECOSYSTEM","ev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