cbcvebase.
CVE-2024-35870
published 2024-05-19

CVE-2024-35870: In the Linux kernel, the following vulnerability has been resolved: smb: client: fix UAF in smb2_reconnect_server() The UAF bug is due to…

PriorityP350critical9.8CVSS 3.1
AVNACLPRNUINSUCHIHAH
EPSS
0.62%
49.0th percentile
In the Linux kernel, the following vulnerability has been resolved: smb: client: fix UAF in smb2_reconnect_server() The UAF bug is due to smb2_reconnect_server() accessing a session that is already being teared down by another thread that is executing __cifs_put_smb_ses(). This can happen when (a) the client has connection to the server but no session or (b) another thread ends up setting @ses->ses_status again to something different than SES_EXITING. To fix this, we need to make sure to unconditionally set @ses->ses_status to SES_EXITING and prevent any other threads from setting a new status while we're still tearing it down. The following can be reproduced by adding some delay to right after the ipc is freed in __cifs_put_smb_ses() - which will give smb2_reconnect_server() worker a chance to run and then accessing @ses->ipc: kinit ... mount.cifs //srv/share /mnt/1 -o sec=krb5,nohandlecache,echo_interval=10 [disconnect srv] ls /mnt/1 &>/dev/null sleep 30 kdestroy [reconnect srv] sleep 10 umount /mnt/1 ... CIFS: VFS: Verify user has a krb5 ticket and keyutils is installed CIFS: VFS: \\srv Send error in SessSetup = -126 CIFS: VFS: Verify user has a krb5 ticket and keyutils is installed CIFS: VFS: \\srv Send error in SessSetup = -126 general protection fault, probably for non-canonical address 0x6b6b6b6b6b6b6b6b: 0000 [#1] PREEMPT SMP NOPTI CPU: 3 PID: 50 Comm: kworker/3:1 Not tainted 6.9.0-rc2 #1 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-1.fc39 04/01/2014 Workqueue: cifsiod smb2_reconnect_server [cifs] RIP: 0010:__list_del_entry_valid_or_report+0x33/0xf0 Code: 4f 08 48 85 d2 74 42 48 85 c9 74 59 48 b8 00 01 00 00 00 00 ad de 48 39 c2 74 61 48 b8 22 01 00 00 00 00 74 69 8b 01 48 39 f8 75 7b 48 8b 72 08 48 39 c6 0f 85 88 00 00 00 b8 RSP: 0018:ffffc900001bfd70 EFLAGS: 00010a83 RAX: dead000000000122 RBX: ffff88810da53838 RCX: 6b6b6b6b6b6b6b6b RDX: 6b6b6b6b6b6b6b6b RSI: ffffffffc02f6878 RDI: ffff88810da53800 RBP: ffff88810da53800 R08: 000000000

Affected

17 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>= b327a717e506980399464e304e363f94f95eb7a1 < 755fe68cd4b59e1d2a2dd3286177fd4404f57fed755fe68cd4b59e1d2a2dd3286177fd4404f57fed
linuxlinux>= b327a717e506980399464e304e363f94f95eb7a1 < 6202996a1c1887e83d0b3b0fcd86d0e5e6910ea06202996a1c1887e83d0b3b0fcd86d0e5e6910ea0
linuxlinux>= b327a717e506980399464e304e363f94f95eb7a1 < 45f2beda1f1bc3d962ec07db1ccc3197c25499a545f2beda1f1bc3d962ec07db1ccc3197c25499a5
linuxlinux>= b327a717e506980399464e304e363f94f95eb7a1 < 24a9799aa8efecd0eb55a75e35f9d8e6400063aa24a9799aa8efecd0eb55a75e35f9d8e6400063aa
linuxlinux_kernel< 6.1.1216.1.121
linuxlinux_kernel——
linuxlinux_kernel——
linuxlinux_kernel>= 0 < 6.1.123-16.1.123-1
linuxlinux_kernel>= 0 < 6.8.9-16.8.9-1
linuxlinux_kernel>= 0 < 6.8.9-16.8.9-1
linuxlinux_kernel>= 0 < 6.8.0-38.386.8.0-38.38
linuxlinux_kernel>= 6.2 < 6.6.296.6.29
linuxlinux_kernel>= 6.7 < 6.8.56.8.5
msrccbl2_kernel_5.15.182.1-1_on_cbl_mariner_2.0——

CVSS provenance

nvdv3.19.8CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
osv6.8MEDIUM
vendor_ubuntu4.6MEDIUM
vendor_debian4.4MEDIUM
vendor_msrc4.4MEDIUM
vendor_redhat4.4MEDIUM
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