cbcvebase.
CVE-2025-21796
published 2025-02-27

CVE-2025-21796: In the Linux kernel, the following vulnerability has been resolved: nfsd: clear acl_access/acl_default after releasing them If getting acl_default fails…

PriorityP350critical9.8CVSS 3.1
AVNACLPRNUINSUCHIHAH
EPSS
0.67%
51.8th percentile
In the Linux kernel, the following vulnerability has been resolved: nfsd: clear acl_access/acl_default after releasing them If getting acl_default fails, acl_access and acl_default will be released simultaneously. However, acl_access will still retain a pointer pointing to the released posix_acl, which will trigger a WARNING in nfs3svc_release_getacl like this: ------------[ cut here ]------------ refcount_t: underflow; use-after-free. WARNING: CPU: 26 PID: 3199 at lib/refcount.c:28 refcount_warn_saturate+0xb5/0x170 Modules linked in: CPU: 26 UID: 0 PID: 3199 Comm: nfsd Not tainted 6.12.0-rc6-00079-g04ae226af01f-dirty #8 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.1-2.fc37 04/01/2014 RIP: 0010:refcount_warn_saturate+0xb5/0x170 Code: cc cc 0f b6 1d b3 20 a5 03 80 fb 01 0f 87 65 48 d8 00 83 e3 01 75 e4 48 c7 c7 c0 3b 9b 85 c6 05 97 20 a5 03 01 e8 fb 3e 30 ff 0b eb cd 0f b6 1d 8a3 RSP: 0018:ffffc90008637cd8 EFLAGS: 00010282 RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffffffff83904fde RDX: dffffc0000000000 RSI: 0000000000000008 RDI: ffff88871ed36380 RBP: ffff888158beeb40 R08: 0000000000000001 R09: fffff520010c6f56 R10: ffffc90008637ab7 R11: 0000000000000001 R12: 0000000000000001 R13: ffff888140e77400 R14: ffff888140e77408 R15: ffffffff858b42c0 FS: 0000000000000000(0000) GS:ffff88871ed00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000562384d32158 CR3: 000000055cc6a000 CR4: 00000000000006f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: ? refcount_warn_saturate+0xb5/0x170 ? __warn+0xa5/0x140 ? refcount_warn_saturate+0xb5/0x170 ? report_bug+0x1b1/0x1e0 ? handle_bug+0x53/0xa0 ? exc_invalid_op+0x17/0x40 ? asm_exc_invalid_op+0x1a/0x20 ? tick_nohz_tick_stopped+0x1e/0x40 ? refcount_warn_saturate+0xb5/0x170 ? refcount_warn_saturate+0xb5/0x170 nfs3svc_release_getacl+0xc9/0xe0 svc_process_common+0x5db/0xb60 ? __pf

Affected

31 ranges· showing 25
VendorProductVersion rangeFixed in
debianlinux< linux 6.1.129-1 (bookworm)linux 6.1.129-1 (bookworm)
debianlinux-6.1< linux 6.1.129-1 (bookworm)linux 6.1.129-1 (bookworm)
linuxlinux——
linuxlinux>= a257cdd0e2179630d3201c32ba14d7fcb3c3a055 < 8a1737ae42c928384ab6447f6ee1a882510e85fa8a1737ae42c928384ab6447f6ee1a882510e85fa
linuxlinux>= a257cdd0e2179630d3201c32ba14d7fcb3c3a055 < 6f7cfee1a316891890c505563aa54f3476db52fd6f7cfee1a316891890c505563aa54f3476db52fd
linuxlinux>= a257cdd0e2179630d3201c32ba14d7fcb3c3a055 < 2e59b2b68782519560b3d6a41dd66a3d01a01cd32e59b2b68782519560b3d6a41dd66a3d01a01cd3
linuxlinux>= a257cdd0e2179630d3201c32ba14d7fcb3c3a055 < 55d947315fb5f67a35e4e1d3e01bb886b9c6decf55d947315fb5f67a35e4e1d3e01bb886b9c6decf
linuxlinux>= a257cdd0e2179630d3201c32ba14d7fcb3c3a055 < f8d871523142f7895f250a856f8c4a4181614510f8d871523142f7895f250a856f8c4a4181614510
linuxlinux>= a257cdd0e2179630d3201c32ba14d7fcb3c3a055 < 1fd94884174bd20beb1773990fd3b1aa877688d91fd94884174bd20beb1773990fd3b1aa877688d9
linuxlinux>= a257cdd0e2179630d3201c32ba14d7fcb3c3a055 < 7faf14a7b0366f153284db0ad3347c457ea701367faf14a7b0366f153284db0ad3347c457ea70136
linuxlinux_kernel——
linuxlinux_kernel——
linuxlinux_kernel>= 0 < 5.10.237-15.10.237-1
linuxlinux_kernel>= 0 < 6.1.129-16.1.129-1
linuxlinux_kernel>= 0 < 6.12.16-16.12.16-1
linuxlinux_kernel>= 0 < 6.12.16-16.12.16-1
linuxlinux_kernel>= 0 < 5.15.0-140.1505.15.0-140.150
linuxlinux_kernel>= 0 < 6.8.0-78.786.8.0-78.78
linuxlinux_kernel>= 0 < 4.4.0-273.3074.4.0-273.307
linuxlinux_kernel>= 0 < 4.15.0-242.2544.15.0-242.254
linuxlinux_kernel>= 0 < 5.4.0-222.2425.4.0-222.242
linuxlinux_kernel>= 2.6.13 < 5.10.2355.10.235
linuxlinux_kernel>= 5.11 < 5.15.1795.15.179
linuxlinux_kernel>= 5.16 < 6.1.1296.1.129
linuxlinux_kernel>= 6.13 < 6.13.46.13.4

CVSS provenance

nvdv3.19.8CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
osv8.8HIGH
vendor_ubuntu8.8HIGH
vendor_debian7.8HIGH
vendor_redhat7.8HIGH
vendor_msrc6.6MEDIUM
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