{"id":"DEBIAN-CVE-2025-21887","details":"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-\u003ed_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:  \u003cTASK\u003e  __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 ...  \u003c/TASK\u003e","modified":"2026-09-01T16:06:10.285234547Z","published":"2025-03-27T15:15:56.603Z","upstream":["CVE-2025-21887"],"references":[{"type":"ADVISORY","url":"https://security-tracker.debian.org/tracker/CVE-2025-21887"}],"affected":[{"package":{"name":"linux","ecosystem":"Debian:12","purl":"pkg:deb/debian/linux?arch=source&distro=bookworm"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"6.1.133-1"}]}],"versions":["6.1.106-1","6.1.106-2","6.1.106-3","6.1.112-1","6.1.115-1","6.1.119-1","6.1.123-1","6.1.124-1","6.1.128-1","6.1.129-1","6.1.27-1","6.1.37-1","6.1.38-1","6.1.38-2","6.1.38-2~bpo11+1","6.1.38-3","6.1.38-4","6.1.38-4~bpo11+1","6.1.52-1","6.1.55-1","6.1.55-1~bpo11+1","6.1.64-1","6.1.66-1","6.1.67-1","6.1.69-1","6.1.69-1~bpo11+1","6.1.76-1","6.1.76-1~bpo11+1","6.1.82-1","6.1.85-1","6.1.90-1","6.1.90-1~bpo11+1","6.1.94-1","6.1.94-1~bpo11+1","6.1.98-1","6.1.99-1"],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2025-21887.json"}},{"package":{"name":"linux","ecosystem":"Debian:13","purl":"pkg:deb/debian/linux?arch=source&distro=trixie"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"6.12.19-1"}]}],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2025-21887.json"}},{"package":{"name":"linux","ecosystem":"Debian:14","purl":"pkg:deb/debian/linux?arch=source&distro=forky"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"6.12.19-1"}]}],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2025-21887.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H"}]}