{"id":"DEBIAN-CVE-2026-23428","details":"In the Linux kernel, the following vulnerability has been resolved:  ksmbd: fix use-after-free of share_conf in compound request  smb2_get_ksmbd_tcon() reuses work-\u003etcon in compound requests without validating tcon-\u003et_state. ksmbd_tree_conn_lookup() checks t_state == TREE_CONNECTED on the initial lookup path, but the compound reuse path bypasses this check entirely.  If a prior command in the compound (SMB2_TREE_DISCONNECT) sets t_state to TREE_DISCONNECTED and frees share_conf via ksmbd_share_config_put(), subsequent commands dereference the freed share_conf through work-\u003etcon-\u003eshare_conf.  KASAN report:  [    4.144653] ================================================================== [    4.145059] BUG: KASAN: slab-use-after-free in smb2_write+0xc74/0xe70 [    4.145415] Read of size 4 at addr ffff88810430c194 by task kworker/1:1/44 [    4.145772] [    4.145867] CPU: 1 UID: 0 PID: 44 Comm: kworker/1:1 Not tainted 7.0.0-rc3+ #60 PREEMPTLAZY [    4.145871] Hardware name: QEMU Ubuntu 24.04 PC v2 (i440FX + PIIX, arch_caps fix, 1996), BIOS 1.16.3-debian-1.16.3-2 04/01/2014 [    4.145875] Workqueue: ksmbd-io handle_ksmbd_work [    4.145888] Call Trace: [    4.145892]  \u003cTASK\u003e [    4.145894]  dump_stack_lvl+0x64/0x80 [    4.145910]  print_report+0xce/0x660 [    4.145919]  ? __pfx__raw_spin_lock_irqsave+0x10/0x10 [    4.145928]  ? smb2_write+0xc74/0xe70 [    4.145931]  kasan_report+0xce/0x100 [    4.145934]  ? smb2_write+0xc74/0xe70 [    4.145937]  smb2_write+0xc74/0xe70 [    4.145939]  ? __pfx_smb2_write+0x10/0x10 [    4.145942]  ? _raw_spin_unlock+0xe/0x30 [    4.145945]  ? ksmbd_smb2_check_message+0xeb2/0x24c0 [    4.145948]  ? smb2_tree_disconnect+0x31c/0x480 [    4.145951]  handle_ksmbd_work+0x40f/0x1080 [    4.145953]  process_one_work+0x5fa/0xef0 [    4.145962]  ? assign_work+0x122/0x3e0 [    4.145964]  worker_thread+0x54b/0xf70 [    4.145967]  ? __pfx_worker_thread+0x10/0x10 [    4.145970]  kthread+0x346/0x470 [    4.145976]  ? recalc_sigpending+0x19b/0x230 [    4.145980]  ? __pfx_kthread+0x10/0x10 [    4.145984]  ret_from_fork+0x4fb/0x6c0 [    4.145992]  ? __pfx_ret_from_fork+0x10/0x10 [    4.145995]  ? __switch_to+0x36c/0xbe0 [    4.145999]  ? __pfx_kthread+0x10/0x10 [    4.146003]  ret_from_fork_asm+0x1a/0x30 [    4.146013]  \u003c/TASK\u003e [    4.146014] [    4.149858] Allocated by task 44: [    4.149953]  kasan_save_stack+0x33/0x60 [    4.150061]  kasan_save_track+0x14/0x30 [    4.150169]  __kasan_kmalloc+0x8f/0xa0 [    4.150274]  ksmbd_share_config_get+0x1dd/0xdd0 [    4.150401]  ksmbd_tree_conn_connect+0x7e/0x600 [    4.150529]  smb2_tree_connect+0x2e6/0x1000 [    4.150645]  handle_ksmbd_work+0x40f/0x1080 [    4.150761]  process_one_work+0x5fa/0xef0 [    4.150873]  worker_thread+0x54b/0xf70 [    4.150978]  kthread+0x346/0x470 [    4.151071]  ret_from_fork+0x4fb/0x6c0 [    4.151176]  ret_from_fork_asm+0x1a/0x30 [    4.151286] [    4.151332] Freed by task 44: [    4.151418]  kasan_save_stack+0x33/0x60 [    4.151526]  kasan_save_track+0x14/0x30 [    4.151634]  kasan_save_free_info+0x3b/0x60 [    4.151751]  __kasan_slab_free+0x43/0x70 [    4.151861]  kfree+0x1ca/0x430 [    4.151952]  __ksmbd_tree_conn_disconnect+0xc8/0x190 [    4.152088]  smb2_tree_disconnect+0x1cd/0x480 [    4.152211]  handle_ksmbd_work+0x40f/0x1080 [    4.152326]  process_one_work+0x5fa/0xef0 [    4.152438]  worker_thread+0x54b/0xf70 [    4.152545]  kthread+0x346/0x470 [    4.152638]  ret_from_fork+0x4fb/0x6c0 [    4.152743]  ret_from_fork_asm+0x1a/0x30 [    4.152853] [    4.152900] The buggy address belongs to the object at ffff88810430c180 [    4.152900]  which belongs to the cache kmalloc-96 of size 96 [    4.153226] The buggy address is located 20 bytes inside of [    4.153226]  freed 96-byte region [ffff88810430c180, ffff88810430c1e0) [    4.153549] [    4.153596] The buggy address belongs to the physical page: [    4.153750] page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff88810430ce80 pfn:0x10430c [    4.154000] flags: 0x ---truncated---","modified":"2026-09-01T16:06:35.698351527Z","published":"2026-04-03T16:16:23.993Z","upstream":["CVE-2026-23428"],"references":[{"type":"ADVISORY","url":"https://security-tracker.debian.org/tracker/CVE-2026-23428"}],"affected":[{"package":{"name":"linux","ecosystem":"Debian:12","purl":"pkg:deb/debian/linux?arch=source&distro=bookworm"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"6.1.170-1"}]}],"versions":["6.1.106-1","6.1.106-2","6.1.106-3","6.1.112-1","6.1.115-1","6.1.119-1","6.1.123-1","6.1.124-1","6.1.128-1","6.1.129-1","6.1.133-1","6.1.135-1","6.1.137-1","6.1.139-1","6.1.140-1","6.1.147-1","6.1.148-1","6.1.153-1","6.1.158-1","6.1.159-1","6.1.162-1","6.1.164-1","6.1.27-1","6.1.37-1","6.1.38-1","6.1.38-2","6.1.38-2~bpo11+1","6.1.38-3","6.1.38-4","6.1.38-4~bpo11+1","6.1.52-1","6.1.55-1","6.1.55-1~bpo11+1","6.1.64-1","6.1.66-1","6.1.67-1","6.1.69-1","6.1.69-1~bpo11+1","6.1.76-1","6.1.76-1~bpo11+1","6.1.82-1","6.1.85-1","6.1.90-1","6.1.90-1~bpo11+1","6.1.94-1","6.1.94-1~bpo11+1","6.1.98-1","6.1.99-1"],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2026-23428.json"}},{"package":{"name":"linux","ecosystem":"Debian:13","purl":"pkg:deb/debian/linux?arch=source&distro=trixie"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"6.12.85-1"}]}],"versions":["6.12.38-1","6.12.41-1","6.12.43-1","6.12.43-1~bpo12+1","6.12.48-1","6.12.57-1","6.12.57-1~bpo12+1","6.12.63-1","6.12.63-1~bpo12+1","6.12.69-1","6.12.69-1~bpo12+1","6.12.73-1","6.12.73-1~bpo12+1","6.12.74-1","6.12.74-2","6.12.74-2~bpo12+1","6.12.85-1~bpo12+1"],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2026-23428.json"}},{"package":{"name":"linux","ecosystem":"Debian:14","purl":"pkg:deb/debian/linux?arch=source&distro=forky"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"6.19.10-1"}]}],"versions":["6.12.100-1","6.12.101-1","6.12.105-1","6.12.107-1","6.12.38-1","6.12.41-1","6.12.43-1","6.12.43-1~bpo12+1","6.12.48-1","6.12.57-1","6.12.57-1~bpo12+1","6.12.63-1","6.12.63-1~bpo12+1","6.12.69-1","6.12.69-1~bpo12+1","6.12.73-1","6.12.73-1~bpo12+1","6.12.74-1","6.12.74-2","6.12.74-2~bpo12+1","6.12.85-1","6.12.85-1~bpo12+1","6.12.86-1","6.12.86-1~bpo12+1","6.12.88-1","6.12.88-1~bpo12+1","6.12.90-1","6.12.90-1~bpo12+1","6.12.90-2","6.12.90-2~bpo12+1","6.12.94-1","6.12.94-1~bpo12+1","6.12.95-1","6.12.95-1~bpo12+1","6.12.96-1","6.13.10-1~exp1","6.13.11-1~exp1","6.13.2-1~exp1","6.13.3-1~exp1","6.13.4-1~exp1","6.13.5-1~exp1","6.13.6-1~exp1","6.13.7-1~exp1","6.13.8-1~exp1","6.13.9-1~exp1","6.13~rc6-1~exp1","6.13~rc7-1~exp1","6.14.3-1~exp1","6.14.5-1~exp1","6.14.6-1~exp1","6.15-1~exp1","6.15.1-1~exp1","6.15.2-1~exp1","6.15.3-1~exp1","6.15.4-1~exp1","6.15.5-1~exp1","6.15.6-1~exp1","6.15~rc7-1~exp1","6.16-1~exp1","6.16.1-1~exp1","6.16.10-1","6.16.11-1","6.16.12-1","6.16.12-1~bpo13+1","6.16.12-2","6.16.3-1","6.16.3-1~bpo13+1","6.16.5-1","6.16.6-1","6.16.7-1","6.16.8-1","6.16.9-1","6.16~rc7-1~exp1","6.17.10-1","6.17.11-1","6.17.12-1","6.17.13-1","6.17.13-1~bpo13+1","6.17.2-1~exp1","6.17.5-1~exp1","6.17.6-1","6.17.7-1","6.17.7-2","6.17.8-1","6.17.8-1~bpo13+1","6.17.9-1","6.18.1-1~exp1","6.18.10-1","6.18.12-1","6.18.12-1~bpo13+1","6.18.13-1","6.18.14-1","6.18.15-1","6.18.15-1~bpo13+1","6.18.2-1~exp1","6.18.3-1","6.18.5-1","6.18.5-1~bpo13+1","6.18.8-1","6.18.9-1","6.18.9-1~bpo13+1","6.18~rc4-1~exp1","6.18~rc4-1~exp2","6.18~rc5-1~exp1","6.18~rc6-1~exp1","6.18~rc7-1~exp1","6.19-1~exp1","6.19.10-1~bpo13+1","6.19.2-1~exp1","6.19.3-1~exp1","6.19.4-1~exp1","6.19.5-1~exp1","6.19.6-1","6.19.6-2","6.19.6-2~bpo13+1","6.19.8-1","6.19.8-1~bpo13+1","6.19~rc4-1~exp1","6.19~rc5-1~exp1","6.19~rc6-1~exp1","6.19~rc7-1~exp1","6.19~rc8-1~exp1"],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2026-23428.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H"}]}