cbcvebase.
CVE-2021-4439
published 2024-06-20

CVE-2021-4439: In the Linux kernel, the following vulnerability has been resolved: isdn: cpai: check ctr->cnr to avoid array index out of bound The cmtp_add_connection()…

PriorityP339high7.8CVSS 3.1
AVLACLPRLUINSUCHIHAH
EPSS
0.24%
14.6th percentile
In the Linux kernel, the following vulnerability has been resolved: isdn: cpai: check ctr->cnr to avoid array index out of bound The cmtp_add_connection() would add a cmtp session to a controller and run a kernel thread to process cmtp. __module_get(THIS_MODULE); session->task = kthread_run(cmtp_session, session, "kcmtpd_ctr_%d", session->num); During this process, the kernel thread would call detach_capi_ctr() to detach a register controller. if the controller was not attached yet, detach_capi_ctr() would trigger an array-index-out-bounds bug. [ 46.866069][ T6479] UBSAN: array-index-out-of-bounds in drivers/isdn/capi/kcapi.c:483:21 [ 46.867196][ T6479] index -1 is out of range for type 'capi_ctr *[32]' [ 46.867982][ T6479] CPU: 1 PID: 6479 Comm: kcmtpd_ctr_0 Not tainted 5.15.0-rc2+ #8 [ 46.869002][ T6479] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.14.0-2 04/01/2014 [ 46.870107][ T6479] Call Trace: [ 46.870473][ T6479] dump_stack_lvl+0x57/0x7d [ 46.870974][ T6479] ubsan_epilogue+0x5/0x40 [ 46.871458][ T6479] __ubsan_handle_out_of_bounds.cold+0x43/0x48 [ 46.872135][ T6479] detach_capi_ctr+0x64/0xc0 [ 46.872639][ T6479] cmtp_session+0x5c8/0x5d0 [ 46.873131][ T6479] ? __init_waitqueue_head+0x60/0x60 [ 46.873712][ T6479] ? cmtp_add_msgpart+0x120/0x120 [ 46.874256][ T6479] kthread+0x147/0x170 [ 46.874709][ T6479] ? set_kthread_struct+0x40/0x40 [ 46.875248][ T6479] ret_from_fork+0x1f/0x30 [ 46.875773][ T6479]

Affected

22 ranges
VendorProductVersion rangeFixed in
debianlinux< linux 5.14.16-1 (bookworm)linux 5.14.16-1 (bookworm)
linuxlinux
linuxlinux>= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < e8b8de17e164c9f1b7777f1c6f99d05539000036e8b8de17e164c9f1b7777f1c6f99d05539000036
linuxlinux>= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 24219a977bfe3d658687e45615c70998acdbac5a24219a977bfe3d658687e45615c70998acdbac5a
linuxlinux>= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 9b6b2db77bc3121fe435f1d4b56e34de443bec759b6b2db77bc3121fe435f1d4b56e34de443bec75
linuxlinux>= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 7d91adc0ccb060ce564103315189466eb822cc6a7d91adc0ccb060ce564103315189466eb822cc6a
linuxlinux>= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 285e9210b1fab96a11c0be3ed5cea9dd48b6ac54285e9210b1fab96a11c0be3ed5cea9dd48b6ac54
linuxlinux>= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 7f221ccbee4ec662e2292d490a43ce6c314c45947f221ccbee4ec662e2292d490a43ce6c314c4594
linuxlinux>= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < cc20226e218a2375d50dd9ac14fb4121b43375ffcc20226e218a2375d50dd9ac14fb4121b43375ff
linuxlinux>= 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 1f3e2e97c003f80c4b087092b225c8787ff91e4d1f3e2e97c003f80c4b087092b225c8787ff91e4d
linuxlinux_kernel< 4.4.2904.4.290
linuxlinux_kernel
linuxlinux_kernel>= 0 < 5.10.84-15.10.84-1
linuxlinux_kernel>= 0 < 5.14.16-15.14.16-1
linuxlinux_kernel>= 0 < 5.14.16-15.14.16-1
linuxlinux_kernel>= 0 < 5.14.16-15.14.16-1
linuxlinux_kernel>= 4.10 < 4.14.2534.14.253
linuxlinux_kernel>= 4.15 < 4.19.2144.19.214
linuxlinux_kernel>= 4.20 < 5.4.1565.4.156
linuxlinux_kernel>= 4.5 < 4.9.2884.9.288
linuxlinux_kernel>= 5.11 < 5.14.155.14.15
linuxlinux_kernel>= 5.5 < 5.10.765.10.76

CVSS provenance

nvdv3.17.8HIGHCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
osv7.8HIGH
vendor_debian7.8HIGH
vendor_redhat7.8HIGH
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