cbcvebase.
CVE-2024-56558
published 2024-12-27

CVE-2024-56558: In the Linux kernel, the following vulnerability has been resolved: nfsd: make sure exp active before svc_export_show The function `e_show` was called with…

PriorityP338high7.8CVSS 3.1
AVLACLPRLUINSUCHIHAH
EPSS
0.24%
14.6th percentile
In the Linux kernel, the following vulnerability has been resolved: nfsd: make sure exp active before svc_export_show The function `e_show` was called with protection from RCU. This only ensures that `exp` will not be freed. Therefore, the reference count for `exp` can drop to zero, which will trigger a refcount use-after-free warning when `exp_get` is called. To resolve this issue, use `cache_get_rcu` to ensure that `exp` remains active. ------------[ cut here ]------------ refcount_t: addition on 0; use-after-free. WARNING: CPU: 3 PID: 819 at lib/refcount.c:25 refcount_warn_saturate+0xb1/0x120 CPU: 3 UID: 0 PID: 819 Comm: cat Not tainted 6.12.0-rc3+ #1 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.1-2.fc37 04/01/2014 RIP: 0010:refcount_warn_saturate+0xb1/0x120 ... Call Trace: e_show+0x20b/0x230 [nfsd] seq_read_iter+0x589/0x770 seq_read+0x1e5/0x270 vfs_read+0x125/0x530 ksys_read+0xc1/0x160 do_syscall_64+0x5f/0x170 entry_SYSCALL_64_after_hwframe+0x76/0x7e

Affected

23 ranges
VendorProductVersion rangeFixed in
debianlinux< linux 6.1.123-1 (bookworm)linux 6.1.123-1 (bookworm)
debianlinux-6.1< linux 6.1.123-1 (bookworm)linux 6.1.123-1 (bookworm)
linuxlinux
linuxlinux>= bf18f163e89c52e09c96534db45c4274273a0b34 < e2fa0d0e327279a8defb87b263cd0bf288fd9261e2fa0d0e327279a8defb87b263cd0bf288fd9261
linuxlinux>= bf18f163e89c52e09c96534db45c4274273a0b34 < 7fd29d284b55c2274f7a748e6c5f25b4758b8da57fd29d284b55c2274f7a748e6c5f25b4758b8da5
linuxlinux>= bf18f163e89c52e09c96534db45c4274273a0b34 < 6cefcadd34e3c71c81ea64b899a0daa86314a51a6cefcadd34e3c71c81ea64b899a0daa86314a51a
linuxlinux>= bf18f163e89c52e09c96534db45c4274273a0b34 < 7d8f7816bebcd2e7400bb4d786eccb8f33c9f9ec7d8f7816bebcd2e7400bb4d786eccb8f33c9f9ec
linuxlinux>= bf18f163e89c52e09c96534db45c4274273a0b34 < 1cecfdbc6bfc89c516d286884c7f29267b95de2b1cecfdbc6bfc89c516d286884c7f29267b95de2b
linuxlinux>= bf18f163e89c52e09c96534db45c4274273a0b34 < 7365d1f8de63cffdbbaa2287ce0205438e1a922f7365d1f8de63cffdbbaa2287ce0205438e1a922f
linuxlinux>= bf18f163e89c52e09c96534db45c4274273a0b34 < be8f982c369c965faffa198b46060f8853e0f1f0be8f982c369c965faffa198b46060f8853e0f1f0
linuxlinux_kernel>= 0 < 5.10.234-15.10.234-1
linuxlinux_kernel>= 0 < 6.1.123-16.1.123-1
linuxlinux_kernel>= 0 < 6.12.5-16.12.5-1
linuxlinux_kernel>= 0 < 6.12.5-16.12.5-1
linuxlinux_kernel>= 0 < 5.4.0-211.2315.4.0-211.231
linuxlinux_kernel>= 0 < 5.15.0-135.1465.15.0-135.146
linuxlinux_kernel>= 0 < 6.8.0-58.606.8.0-58.60
linuxlinux_kernel>= 3.17 < 5.4.2875.4.287
linuxlinux_kernel>= 5.11 < 5.15.1745.15.174
linuxlinux_kernel>= 5.16 < 6.1.1206.1.120
linuxlinux_kernel>= 5.5 < 5.10.2315.10.231
linuxlinux_kernel>= 6.2 < 6.6.646.6.64
linuxlinux_kernel>= 6.7 < 6.12.46.12.4

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_redhat7.8HIGH
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