{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-23428", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-01-13T15:37:46.016Z", "datePublished": "2026-04-03T15:15:14.981Z", "dateUpdated": "2026-04-03T15:15:14.981Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-04-03T15:15:14.981Z"}, "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nksmbd: fix use-after-free of share_conf in compound request\n\nsmb2_get_ksmbd_tcon() reuses work->tcon in compound requests without\nvalidating tcon->t_state. ksmbd_tree_conn_lookup() checks t_state ==\nTREE_CONNECTED on the initial lookup path, but the compound reuse path\nbypasses this check entirely.\n\nIf a prior command in the compound (SMB2_TREE_DISCONNECT) sets t_state\nto TREE_DISCONNECTED and frees share_conf via ksmbd_share_config_put(),\nsubsequent commands dereference the freed share_conf through\nwork->tcon->share_conf.\n\nKASAN report:\n\n[ 4.144653] ==================================================================\n[ 4.145059] BUG: KASAN: slab-use-after-free in smb2_write+0xc74/0xe70\n[ 4.145415] Read of size 4 at addr ffff88810430c194 by task kworker/1:1/44\n[ 4.145772]\n[ 4.145867] CPU: 1 UID: 0 PID: 44 Comm: kworker/1:1 Not tainted 7.0.0-rc3+ #60 PREEMPTLAZY\n[ 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\n[ 4.145875] Workqueue: ksmbd-io handle_ksmbd_work\n[ 4.145888] Call Trace:\n[ 4.145892] <TASK>\n[ 4.145894] dump_stack_lvl+0x64/0x80\n[ 4.145910] print_report+0xce/0x660\n[ 4.145919] ? __pfx__raw_spin_lock_irqsave+0x10/0x10\n[ 4.145928] ? smb2_write+0xc74/0xe70\n[ 4.145931] kasan_report+0xce/0x100\n[ 4.145934] ? smb2_write+0xc74/0xe70\n[ 4.145937] smb2_write+0xc74/0xe70\n[ 4.145939] ? __pfx_smb2_write+0x10/0x10\n[ 4.145942] ? _raw_spin_unlock+0xe/0x30\n[ 4.145945] ? ksmbd_smb2_check_message+0xeb2/0x24c0\n[ 4.145948] ? smb2_tree_disconnect+0x31c/0x480\n[ 4.145951] handle_ksmbd_work+0x40f/0x1080\n[ 4.145953] process_one_work+0x5fa/0xef0\n[ 4.145962] ? assign_work+0x122/0x3e0\n[ 4.145964] worker_thread+0x54b/0xf70\n[ 4.145967] ? __pfx_worker_thread+0x10/0x10\n[ 4.145970] kthread+0x346/0x470\n[ 4.145976] ? recalc_sigpending+0x19b/0x230\n[ 4.145980] ? __pfx_kthread+0x10/0x10\n[ 4.145984] ret_from_fork+0x4fb/0x6c0\n[ 4.145992] ? __pfx_ret_from_fork+0x10/0x10\n[ 4.145995] ? __switch_to+0x36c/0xbe0\n[ 4.145999] ? __pfx_kthread+0x10/0x10\n[ 4.146003] ret_from_fork_asm+0x1a/0x30\n[ 4.146013] </TASK>\n[ 4.146014]\n[ 4.149858] Allocated by task 44:\n[ 4.149953] kasan_save_stack+0x33/0x60\n[ 4.150061] kasan_save_track+0x14/0x30\n[ 4.150169] __kasan_kmalloc+0x8f/0xa0\n[ 4.150274] ksmbd_share_config_get+0x1dd/0xdd0\n[ 4.150401] ksmbd_tree_conn_connect+0x7e/0x600\n[ 4.150529] smb2_tree_connect+0x2e6/0x1000\n[ 4.150645] handle_ksmbd_work+0x40f/0x1080\n[ 4.150761] process_one_work+0x5fa/0xef0\n[ 4.150873] worker_thread+0x54b/0xf70\n[ 4.150978] kthread+0x346/0x470\n[ 4.151071] ret_from_fork+0x4fb/0x6c0\n[ 4.151176] ret_from_fork_asm+0x1a/0x30\n[ 4.151286]\n[ 4.151332] Freed by task 44:\n[ 4.151418] kasan_save_stack+0x33/0x60\n[ 4.151526] kasan_save_track+0x14/0x30\n[ 4.151634] kasan_save_free_info+0x3b/0x60\n[ 4.151751] __kasan_slab_free+0x43/0x70\n[ 4.151861] kfree+0x1ca/0x430\n[ 4.151952] __ksmbd_tree_conn_disconnect+0xc8/0x190\n[ 4.152088] smb2_tree_disconnect+0x1cd/0x480\n[ 4.152211] handle_ksmbd_work+0x40f/0x1080\n[ 4.152326] process_one_work+0x5fa/0xef0\n[ 4.152438] worker_thread+0x54b/0xf70\n[ 4.152545] kthread+0x346/0x470\n[ 4.152638] ret_from_fork+0x4fb/0x6c0\n[ 4.152743] ret_from_fork_asm+0x1a/0x30\n[ 4.152853]\n[ 4.152900] The buggy address belongs to the object at ffff88810430c180\n[ 4.152900] which belongs to the cache kmalloc-96 of size 96\n[ 4.153226] The buggy address is located 20 bytes inside of\n[ 4.153226] freed 96-byte region [ffff88810430c180, ffff88810430c1e0)\n[ 4.153549]\n[ 4.153596] The buggy address belongs to the physical page:\n[ 4.153750] page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff88810430ce80 pfn:0x10430c\n[ 4.154000] flags: 0x\n---truncated---"}], "affected": [{"product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["fs/smb/server/smb2pdu.c"], "versions": [{"version": "854156d12caa9d36de1cf5f084591c7686cc8a9d", "lessThan": "eae0dc86f71e6f3294c0cd7ffc05039258d243af", "status": "affected", "versionType": "git"}, {"version": "5005bcb4219156f1bf7587b185080ec1da08518e", "lessThan": "806f13752652216db0c309392b4db3e64eeed4f2", "status": "affected", "versionType": "git"}, {"version": "5005bcb4219156f1bf7587b185080ec1da08518e", "lessThan": "c742b46a153d3ff95ff0825ab1950c87b9e14470", "status": "affected", "versionType": "git"}, {"version": "5005bcb4219156f1bf7587b185080ec1da08518e", "lessThan": "7f7468fd2a7554cea91b7d430335a3dbf01dcc09", "status": "affected", "versionType": "git"}, {"version": "5005bcb4219156f1bf7587b185080ec1da08518e", "lessThan": "a5929c2020ce54e1dcbd1078c0f30b8aaf73c105", "status": "affected", "versionType": "git"}, {"version": "5005bcb4219156f1bf7587b185080ec1da08518e", "lessThan": "c33615f995aee80657b9fdfbc4ee7f49c2bd733d", "status": "affected", "versionType": "git"}, {"version": "eb947403518ea3d93f6d89264bb1f5416bb0c7d0", "status": "affected", "versionType": "git"}, {"version": "d1066c1b3663401cd23c0d6e60cdae750ce00c0f", "status": "affected", "versionType": "git"}]}, {"product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["fs/smb/server/smb2pdu.c"], "versions": [{"version": "6.4", "status": "affected"}, {"version": "0", "lessThan": "6.4", "status": "unaffected", "versionType": "semver"}, {"version": "6.1.167", "lessThanOrEqual": "6.1.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.6.130", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.12.78", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.18.20", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.19.10", "lessThanOrEqual": "6.19.*", "status": "unaffected", "versionType": "semver"}, {"version": "7.0-rc5", "lessThanOrEqual": "*", "status": "unaffected", "versionType": "original_commit_for_fix"}]}], "cpeApplicability": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.1.36", "versionEndExcluding": "6.1.167"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.4", "versionEndExcluding": "6.6.130"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.4", "versionEndExcluding": "6.12.78"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.4", "versionEndExcluding": "6.18.20"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.4", "versionEndExcluding": "6.19.10"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.4", "versionEndExcluding": "7.0-rc5"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.15.121"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.3.10"}]}]}], "references": [{"url": "https://git.kernel.org/stable/c/eae0dc86f71e6f3294c0cd7ffc05039258d243af"}, {"url": "https://git.kernel.org/stable/c/806f13752652216db0c309392b4db3e64eeed4f2"}, {"url": "https://git.kernel.org/stable/c/c742b46a153d3ff95ff0825ab1950c87b9e14470"}, {"url": "https://git.kernel.org/stable/c/7f7468fd2a7554cea91b7d430335a3dbf01dcc09"}, {"url": "https://git.kernel.org/stable/c/a5929c2020ce54e1dcbd1078c0f30b8aaf73c105"}, {"url": "https://git.kernel.org/stable/c/c33615f995aee80657b9fdfbc4ee7f49c2bd733d"}], "title": "ksmbd: fix use-after-free of share_conf in compound request", "x_generator": {"engine": "bippy-1.2.0"}}}}

{}

{"cveTags": [], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nksmbd: fix use-after-free of share_conf in compound request\n\nsmb2_get_ksmbd_tcon() reuses work->tcon in compound requests without\nvalidating tcon->t_state. ksmbd_tree_conn_lookup() checks t_state ==\nTREE_CONNECTED on the initial lookup path, but the compound reuse path\nbypasses this check entirely.\n\nIf a prior command in the compound (SMB2_TREE_DISCONNECT) sets t_state\nto TREE_DISCONNECTED and frees share_conf via ksmbd_share_config_put(),\nsubsequent commands dereference the freed share_conf through\nwork->tcon->share_conf.\n\nKASAN report:\n\n[ 4.144653] ==================================================================\n[ 4.145059] BUG: KASAN: slab-use-after-free in smb2_write+0xc74/0xe70\n[ 4.145415] Read of size 4 at addr ffff88810430c194 by task kworker/1:1/44\n[ 4.145772]\n[ 4.145867] CPU: 1 UID: 0 PID: 44 Comm: kworker/1:1 Not tainted 7.0.0-rc3+ #60 PREEMPTLAZY\n[ 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\n[ 4.145875] Workqueue: ksmbd-io handle_ksmbd_work\n[ 4.145888] Call Trace:\n[ 4.145892] <TASK>\n[ 4.145894] dump_stack_lvl+0x64/0x80\n[ 4.145910] print_report+0xce/0x660\n[ 4.145919] ? __pfx__raw_spin_lock_irqsave+0x10/0x10\n[ 4.145928] ? smb2_write+0xc74/0xe70\n[ 4.145931] kasan_report+0xce/0x100\n[ 4.145934] ? smb2_write+0xc74/0xe70\n[ 4.145937] smb2_write+0xc74/0xe70\n[ 4.145939] ? __pfx_smb2_write+0x10/0x10\n[ 4.145942] ? _raw_spin_unlock+0xe/0x30\n[ 4.145945] ? ksmbd_smb2_check_message+0xeb2/0x24c0\n[ 4.145948] ? smb2_tree_disconnect+0x31c/0x480\n[ 4.145951] handle_ksmbd_work+0x40f/0x1080\n[ 4.145953] process_one_work+0x5fa/0xef0\n[ 4.145962] ? assign_work+0x122/0x3e0\n[ 4.145964] worker_thread+0x54b/0xf70\n[ 4.145967] ? __pfx_worker_thread+0x10/0x10\n[ 4.145970] kthread+0x346/0x470\n[ 4.145976] ? recalc_sigpending+0x19b/0x230\n[ 4.145980] ? __pfx_kthread+0x10/0x10\n[ 4.145984] ret_from_fork+0x4fb/0x6c0\n[ 4.145992] ? __pfx_ret_from_fork+0x10/0x10\n[ 4.145995] ? __switch_to+0x36c/0xbe0\n[ 4.145999] ? __pfx_kthread+0x10/0x10\n[ 4.146003] ret_from_fork_asm+0x1a/0x30\n[ 4.146013] </TASK>\n[ 4.146014]\n[ 4.149858] Allocated by task 44:\n[ 4.149953] kasan_save_stack+0x33/0x60\n[ 4.150061] kasan_save_track+0x14/0x30\n[ 4.150169] __kasan_kmalloc+0x8f/0xa0\n[ 4.150274] ksmbd_share_config_get+0x1dd/0xdd0\n[ 4.150401] ksmbd_tree_conn_connect+0x7e/0x600\n[ 4.150529] smb2_tree_connect+0x2e6/0x1000\n[ 4.150645] handle_ksmbd_work+0x40f/0x1080\n[ 4.150761] process_one_work+0x5fa/0xef0\n[ 4.150873] worker_thread+0x54b/0xf70\n[ 4.150978] kthread+0x346/0x470\n[ 4.151071] ret_from_fork+0x4fb/0x6c0\n[ 4.151176] ret_from_fork_asm+0x1a/0x30\n[ 4.151286]\n[ 4.151332] Freed by task 44:\n[ 4.151418] kasan_save_stack+0x33/0x60\n[ 4.151526] kasan_save_track+0x14/0x30\n[ 4.151634] kasan_save_free_info+0x3b/0x60\n[ 4.151751] __kasan_slab_free+0x43/0x70\n[ 4.151861] kfree+0x1ca/0x430\n[ 4.151952] __ksmbd_tree_conn_disconnect+0xc8/0x190\n[ 4.152088] smb2_tree_disconnect+0x1cd/0x480\n[ 4.152211] handle_ksmbd_work+0x40f/0x1080\n[ 4.152326] process_one_work+0x5fa/0xef0\n[ 4.152438] worker_thread+0x54b/0xf70\n[ 4.152545] kthread+0x346/0x470\n[ 4.152638] ret_from_fork+0x4fb/0x6c0\n[ 4.152743] ret_from_fork_asm+0x1a/0x30\n[ 4.152853]\n[ 4.152900] The buggy address belongs to the object at ffff88810430c180\n[ 4.152900] which belongs to the cache kmalloc-96 of size 96\n[ 4.153226] The buggy address is located 20 bytes inside of\n[ 4.153226] freed 96-byte region [ffff88810430c180, ffff88810430c1e0)\n[ 4.153549]\n[ 4.153596] The buggy address belongs to the physical page:\n[ 4.153750] page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff88810430ce80 pfn:0x10430c\n[ 4.154000] flags: 0x\n---truncated---"}], "id": "CVE-2026-23428", "lastModified": "2026-04-03T16:16:23.993", "metrics": {}, "published": "2026-04-03T16:16:23.993", "references": [{"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/7f7468fd2a7554cea91b7d430335a3dbf01dcc09"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/806f13752652216db0c309392b4db3e64eeed4f2"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/a5929c2020ce54e1dcbd1078c0f30b8aaf73c105"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/c33615f995aee80657b9fdfbc4ee7f49c2bd733d"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/c742b46a153d3ff95ff0825ab1950c87b9e14470"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/eae0dc86f71e6f3294c0cd7ffc05039258d243af"}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "vulnStatus": "Received"}

{}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[854156d12caa9d36de1cf5f084591c7686cc8a9d,eae0dc86f71e6f3294c0cd7ffc05039258d243af)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[5005bcb4219156f1bf7587b185080ec1da08518e,806f13752652216db0c309392b4db3e64eeed4f2)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[5005bcb4219156f1bf7587b185080ec1da08518e,c742b46a153d3ff95ff0825ab1950c87b9e14470)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[5005bcb4219156f1bf7587b185080ec1da08518e,7f7468fd2a7554cea91b7d430335a3dbf01dcc09)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[5005bcb4219156f1bf7587b185080ec1da08518e,a5929c2020ce54e1dcbd1078c0f30b8aaf73c105)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[5005bcb4219156f1bf7587b185080ec1da08518e,c33615f995aee80657b9fdfbc4ee7f49c2bd733d)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "eb947403518ea3d93f6d89264bb1f5416bb0c7d0"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "d1066c1b3663401cd23c0d6e60cdae750ce00c0f"}}], "enrichment": {"confidence": 99.0, "confidence_source": "inferred", "scores": [{"score": 99.0, "source": "inferred"}, {"score": 100.0, "source": "matching"}]}, "original": {"product": "Linux", "source": "cna", "vendor": "Linux"}, "product": "linux_kernel", "vendor": "linux"}, {"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "semver", "value": "6.4"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[0,6.4)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[6.1.167,6.2.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[6.6.130,6.7.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[6.12.78,6.13.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[6.18.20,6.19.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[6.19.10,6.20.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[7.0-rc5,*]"}}], "enrichment": {"confidence": 99.0, "confidence_source": "inferred", "scores": [{"score": 99.0, "source": "inferred"}, {"score": 100.0, "source": "matching"}]}, "original": {"product": "Linux", "source": "cna", "vendor": "Linux"}, "product": "linux_kernel", "vendor": "linux"}], "analysis": {"en": {"generated_at": "2026-04-03T18:29:39.489695+00:00", "value": {"mitigation_remediation": ["Check the current Linux kernel version. If it is earlier than the kernel release that includes the ksmbd use\u2011after\u2011free fix, upgrade the kernel to the latest patched version provided by the distribution or the upstream Linux kernel project.", "After updating, reboot the system to load the new kernel. Verify that the new kernel does not contain the vulnerable code path.", "If a kernel upgrade cannot be performed immediately, consider disabling SMB2 support entirely or restricting SMB traffic to trusted networks to reduce exposure.", "Keep the kernel updated for any future security patches that address similar memory safety issues."], "summary": {"action": "Apply Patch", "impact": "Denial of Service (Kernel Crash)"}, "threat_synthesis": {"affected_systems": "The flaw resides in the ksmbd component of the Linux kernel, affecting any distribution that incorporates the kernel without the patch that fixes this logic error. It impacts all kernel versions prior to the commit that removes the unsafe reuse of the connection object; specific version numbers are not supplied in the advisory.", "description_and_impact": "A use\u2011after\u2011free occurs in the Linux kernel when a compound SMB2 request reuses a connection object after a previous SMB2_TREE_DISCONNECT command has freed its share configuration structure. The memory for the share configuration is released, yet the subsequent operation dereferences the stale pointer, which triggers a kernel memory read error and ultimately crashes the system.", "risk_and_exploitability": "The vulnerability can be triggered over the network by an attacker who can send a crafted sequence of SMB2 commands to a server running the affected kernel. It results in a kernel panic and denial of service. No exploit is presently documented in public repositories, and the flaw is not listed in CISA\u2019s KEV catalog; however, the absence of a practical countermeasure and the high impact of a kernel crash make it a serious threat if the system remains vulnerable."}}}}, "created": "2026-04-03T21:14:10.000436+00:00", "updated": "2026-04-03T21:16:23.417336+00:00", "vendors": ["linux", "linux$PRODUCT$linux_kernel"]}