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CVE-2025-21887
published 2025-03-27

CVE-2025-21887: In the Linux kernel, the following vulnerability has been resolved: ovl: fix UAF in ovl_dentry_update_reval by moving dput() in ovl_link_up The issue was…

PriorityP338high7.8CVSS 3.1
AVLACLPRLUINSUCHIHAH
EPSS
0.19%
8.9th percentile
In the Linux kernel, the following vulnerability has been resolved: ovl: fix UAF in ovl_dentry_update_reval by moving dput() in ovl_link_up The issue was caused by dput(upper) being called before ovl_dentry_update_reval(), while upper->d_flags was still accessed in ovl_dentry_remote(). Move dput(upper) after its last use to prevent use-after-free. BUG: KASAN: slab-use-after-free in ovl_dentry_remote fs/overlayfs/util.c:162 [inline] BUG: KASAN: slab-use-after-free in ovl_dentry_update_reval+0xd2/0xf0 fs/overlayfs/util.c:167 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:114 print_address_description mm/kasan/report.c:377 [inline] print_report+0xc3/0x620 mm/kasan/report.c:488 kasan_report+0xd9/0x110 mm/kasan/report.c:601 ovl_dentry_remote fs/overlayfs/util.c:162 [inline] ovl_dentry_update_reval+0xd2/0xf0 fs/overlayfs/util.c:167 ovl_link_up fs/overlayfs/copy_up.c:610 [inline] ovl_copy_up_one+0x2105/0x3490 fs/overlayfs/copy_up.c:1170 ovl_copy_up_flags+0x18d/0x200 fs/overlayfs/copy_up.c:1223 ovl_rename+0x39e/0x18c0 fs/overlayfs/dir.c:1136 vfs_rename+0xf84/0x20a0 fs/namei.c:4893 ...

Affected

38 ranges· showing 25
VendorProductVersion rangeFixed in
debianlinux< linux 6.1.133-1 (bookworm)linux 6.1.133-1 (bookworm)
debianlinux-6.1< linux 6.1.133-1 (bookworm)linux 6.1.133-1 (bookworm)
linuxlinux
linuxlinux
linuxlinux
linuxlinux>= 5.10.188 < 5.10.2475.10.247
linuxlinux>= 5.15.121 < 5.15.1795.15.179
linuxlinux>= 6.1.39 < 6.1.1306.1.130
linuxlinux>= 6.3.13 < 6.46.4
linuxlinux>= 6.4.4 < 6.56.5
linuxlinux>= 62f29ca45f832e281fc14966ac25f6ff3bd121ca < 4b49d939b5a79117f939b77cc67efae2694d97994b49d939b5a79117f939b77cc67efae2694d9799
linuxlinux>= 714ba10a6dd19752a349e59aa875f3288ccb59b9 < f77618291836168eca99e89cd175256f928f5e64f77618291836168eca99e89cd175256f928f5e64
linuxlinux>= b07d5cc93e1b28df47a72c519d09d0a836043613 < 64455c8051c3aedc71abb7ec8d47c80301f99f0064455c8051c3aedc71abb7ec8d47c80301f99f00
linuxlinux>= b07d5cc93e1b28df47a72c519d09d0a836043613 < 3594aad97e7be2557ca9fa9c931b206b604028c83594aad97e7be2557ca9fa9c931b206b604028c8
linuxlinux>= b07d5cc93e1b28df47a72c519d09d0a836043613 < 60b4b5c1277fc491da9e1e7abab307bfa39c2db760b4b5c1277fc491da9e1e7abab307bfa39c2db7
linuxlinux>= b07d5cc93e1b28df47a72c519d09d0a836043613 < c84e125fff2615b4d9c259e762596134eddd2f27c84e125fff2615b4d9c259e762596134eddd2f27
linuxlinux>= e4f2a1feebb3f209a0fca82aa53507a5b8be4d53 < a7c41830ffcd17b2177a95a9b99b270302090c35a7c41830ffcd17b2177a95a9b99b270302090c35
linuxlinux_kernel
linuxlinux_kernel
linuxlinux_kernel
linuxlinux_kernel
linuxlinux_kernel>= 0 < 5.10.247-15.10.247-1
linuxlinux_kernel>= 0 < 6.1.133-16.1.133-1
linuxlinux_kernel>= 0 < 6.12.19-16.12.19-1
linuxlinux_kernel>= 0 < 6.12.19-16.12.19-1

CVSS provenance

nvdv3.17.8HIGHCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
osv8.8HIGH
vendor_ubuntu8.8HIGH
vendor_debian7.8HIGH
vendor_msrc7.8HIGH
vendor_redhat7.8HIGH
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