# CVE-2023-53427: linux: In the Linux kernel, the following vulnerability has been resolved: cifs: Fix warning and UAF when destroy the MR li... CVE-2023-53427 is fixed in 20 products on 1 platform, first by ALAS2023-2023-138, released March 20, 2023. It is not reported as exploited. Patch Radar priority: High. - Web page: https://patchblox.com/security/cve/CVE-2023-53427 - Priority: High - CVSS: 7.8 (high) - EPSS: 0.0015 - CISA KEV: not listed - Exploited (vendor report): no - Publicly disclosed: no - Published: Mar 20, 2023 ## Description In the Linux kernel, the following vulnerability has been resolved: cifs: Fix warning and UAF when destroy the MR list If the MR allocate failed, the MR recovery work not initialized and list not cleared. Then will be warning and UAF when release the MR: WARNING: CPU: 4 PID: 824 at kernel/workqueue.c:3066 __flush_work.isra.0+0xf7/0x110 CPU: 4 PID: 824 Comm: mount.cifs Not tainted 6.1.0-rc5+ #82 RIP: 0010:__flush_work.isra.0+0xf7/0x110 Call Trace: __cancel_work_timer+0x2ba/0x2e0 smbd_destroy+0x4e1/0x990 _smbd_get_connection+0x1cbd/0x2110 smbd_get_connection+0x21/0x40 cifs_get_tcp_session+0x8ef/0xda0 mount_get_conns+0x60/0x750 cifs_mount+0x103/0xd00 cifs_smb3_do_mount+0x1dd/0xcb0 smb3_get_tree+0x1d5/0x300 vfs_get_tree+0x41/0xf0 path_mount+0x9b3/0xdd0 __x64_sys_mount+0x190/0x1d0 do_syscall_64+0x35/0x80 entry_SYSCALL_64_after_hwframe+0x46/0xb0 BUG: KASAN: use-after-free in smbd_destroy+0x4fc/0x990 Read of size 8 at addr ffff88810b156a08 by task mount.cifs/824 CPU: 4 PID: 824 Comm: mount.cifs Tainted: G W 6.1.0-rc5+ #82 Call Trace: dump_stack_lvl+0x34/0x44 print_report+0x171/0x472 kasan_report+0xad/0x130 smbd_destroy+0x4fc/0x990 _smbd_get_connection+0x1cbd/0x2110 smbd_get_connection+0x21/0x40 cifs_get_tcp_session+0x8ef/0xda0 mount_get_conns+0x60/0x750 cifs_mount+0x103/0xd00 cifs_smb3_do_mount+0x1dd/0xcb0 smb3_get_tree+0x1d5/0x300 vfs_get_tree+0x41/0xf0 path_mount+0x9b3/0xdd0 __x64_sys_mount+0x190/0x1d0 do_syscall_64+0x35/0x80 entry_SYSCALL_64_after_hwframe+0x46/0xb0 Allocated by task 824: kasan_save_stack+0x1e/0x40 kasan_set_track+0x21/0x30 __kasan_kmalloc+0x7a/0x90 _smbd_get_connection+0x1b6f/0x2110 smbd_get_connection+0x21/0x40 cifs_get_tcp_session+0x8ef/0xda0 mount_get_conns+0x60/0x750 cifs_mount+0x103/0xd00 cifs_smb3_do_mount+0x1dd/0xcb0 smb3_get_tree+0x1d5/0x300 vfs_get_tree+0x41/0xf0 path_mount+0x9b3/0xdd0 __x64_sys_mount+0x190/0x1d0 do_syscall_64+0x35/0x80 entry_SYSCALL_64_after_hwframe+0x46/0xb0 Freed by task 824: kasan_save_stack+0x1e/0x40 kasan_set_track+0x21/0x30 kasan_save_free_info+0x2a/0x40 ____kasan_slab_free+0x143/0x1b0 __kmem_cache_free+0xc8/0x330 _smbd_get_connection+0x1c6a/0x2110 smbd_get_connection+0x21/0x40 cifs_get_tcp_session+0x8ef/0xda0 mount_get_conns+0x60/0x750 cifs_mount+0x103/0xd00 cifs_smb3_do_mount+0x1dd/0xcb0 smb3_get_tree+0x1d5/0x300 vfs_get_tree+0x41/0xf0 path_mount+0x9b3/0xdd0 __x64_sys_mount+0x190/0x1d0 do_syscall_64+0x35/0x80 entry_SYSCALL_64_after_hwframe+0x46/0xb0 Let's initialize the MR recovery work before MR allocate to prevent the warning, remove the MRs from the list to prevent the UAF. ## Where it's fixed | Platform | Product | Fixed in | Fix | Released | |---|---|---|---|---| | Linux | bpftool amzn 2023 | 6.1.19-30.43.amzn2023 | [ALAS2023-2023-138](https://patchblox.com/security/data/fix/linux/alas2023-2023-138.md) | Mar 20, 2023 | | Linux | bpftool-debuginfo amzn 2023 | 6.1.19-30.43.amzn2023 | [ALAS2023-2023-138](https://patchblox.com/security/data/fix/linux/alas2023-2023-138.md) | Mar 20, 2023 | | Linux | kernel amzn 2023 | 6.1.19-30.43.amzn2023 | [ALAS2023-2023-138](https://patchblox.com/security/data/fix/linux/alas2023-2023-138.md) | Mar 20, 2023 | | Linux | kernel-debuginfo amzn 2023 | 6.1.19-30.43.amzn2023 | [ALAS2023-2023-138](https://patchblox.com/security/data/fix/linux/alas2023-2023-138.md) | Mar 20, 2023 | | Linux | kernel-debuginfo-common-aarch64 amzn 2023 | 6.1.19-30.43.amzn2023 | [ALAS2023-2023-138](https://patchblox.com/security/data/fix/linux/alas2023-2023-138.md) | Mar 20, 2023 | | Linux | kernel-debuginfo-common-x86_64 amzn 2023 | 6.1.19-30.43.amzn2023 | [ALAS2023-2023-138](https://patchblox.com/security/data/fix/linux/alas2023-2023-138.md) | Mar 20, 2023 | | Linux | kernel-devel amzn 2023 | 6.1.19-30.43.amzn2023 | [ALAS2023-2023-138](https://patchblox.com/security/data/fix/linux/alas2023-2023-138.md) | Mar 20, 2023 | | Linux | kernel-headers amzn 2023 | 6.1.19-30.43.amzn2023 | [ALAS2023-2023-138](https://patchblox.com/security/data/fix/linux/alas2023-2023-138.md) | Mar 20, 2023 | | Linux | kernel-libbpf amzn 2023 | 6.1.19-30.43.amzn2023 | [ALAS2023-2023-138](https://patchblox.com/security/data/fix/linux/alas2023-2023-138.md) | Mar 20, 2023 | | Linux | kernel-libbpf-devel amzn 2023 | 6.1.19-30.43.amzn2023 | [ALAS2023-2023-138](https://patchblox.com/security/data/fix/linux/alas2023-2023-138.md) | Mar 20, 2023 | | Linux | kernel-libbpf-static amzn 2023 | 6.1.19-30.43.amzn2023 | [ALAS2023-2023-138](https://patchblox.com/security/data/fix/linux/alas2023-2023-138.md) | Mar 20, 2023 | | Linux | kernel-livepatch-6.1.19-30.43 amzn 2023 | 1.0-0.amzn2023 | [ALAS2023-2023-138](https://patchblox.com/security/data/fix/linux/alas2023-2023-138.md) | Mar 20, 2023 | | Linux | kernel-tools amzn 2023 | 6.1.19-30.43.amzn2023 | [ALAS2023-2023-138](https://patchblox.com/security/data/fix/linux/alas2023-2023-138.md) | Mar 20, 2023 | | Linux | kernel-tools-debuginfo amzn 2023 | 6.1.19-30.43.amzn2023 | [ALAS2023-2023-138](https://patchblox.com/security/data/fix/linux/alas2023-2023-138.md) | Mar 20, 2023 | | Linux | kernel-tools-devel amzn 2023 | 6.1.19-30.43.amzn2023 | [ALAS2023-2023-138](https://patchblox.com/security/data/fix/linux/alas2023-2023-138.md) | Mar 20, 2023 | | Linux | linux Debian 12.15 (bookworm) | 6.1.20-1 | [DEBIAN-CVE-2023-53427](https://patchblox.com/security/data/fix/linux/debian-cve-2023-53427.md) | Sep 18, 2025 | | Linux | linux Debian 13.5 (trixie) | 6.1.20-1 | [DEBIAN-CVE-2023-53427](https://patchblox.com/security/data/fix/linux/debian-cve-2023-53427.md) | Sep 18, 2025 | | Linux | linux Debian 14 | 6.1.20-1 | [DEBIAN-CVE-2023-53427](https://patchblox.com/security/data/fix/linux/debian-cve-2023-53427.md) | Sep 18, 2025 | | Linux | perf amzn 2023 | 6.1.19-30.43.amzn2023 | [ALAS2023-2023-138](https://patchblox.com/security/data/fix/linux/alas2023-2023-138.md) | Mar 20, 2023 | | Linux | perf-debuginfo amzn 2023 | 6.1.19-30.43.amzn2023 | [ALAS2023-2023-138](https://patchblox.com/security/data/fix/linux/alas2023-2023-138.md) | Mar 20, 2023 | | Linux | python3-perf amzn 2023 | 6.1.19-30.43.amzn2023 | [ALAS2023-2023-138](https://patchblox.com/security/data/fix/linux/alas2023-2023-138.md) | Mar 20, 2023 | | Linux | python3-perf-debuginfo amzn 2023 | 6.1.19-30.43.amzn2023 | [ALAS2023-2023-138](https://patchblox.com/security/data/fix/linux/alas2023-2023-138.md) | Mar 20, 2023 | --- Data as of 2026-11-09T13:31:49Z UTC. Source: Patchblox Patch Radar (https://patchblox.com/security/patch-radar). Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo Free to use with attribution: show "Data: Patchblox Patch Radar" with a link to https://patchblox.com/security/patch-radar. Terms, including what needs a written agreement: https://patchblox.com/security/patch-radar/use-the-data Product names, logos and trademarks shown on Patch Radar belong to their respective owners. They are used only to identify the software each security fix applies to and to help readers find their platform. Their use does not imply any affiliation with, or endorsement by, those owners, and Patchblox is not affiliated with any of them.