CVE-2026-64448 (GCVE-0-2026-64448)
Vulnerability from cvelistv5
Published
2026-07-25 08:51
Modified
2026-10-19 20:38
Severity ?
8.2 (High) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:H
Summary
In the Linux kernel, the following vulnerability has been resolved: smb: client: restrict implied bcc[0] exemption to responses without data area smb2_check_message() has a long-standing quirk that accepts a response whose calculated length is one byte larger than the bytes actually received ("server can return one byte more due to implied bcc[0]"). This was introduced to accommodate servers that omit the trailing bcc[0] overlap byte when no data area is present. However, the exemption is applied unconditionally, regardless of whether the command actually carries a data area (has_smb2_data_area[]). When a response with a data area is subject to the +1 exemption, the reported data can extend one byte beyond the bytes actually received, yet smb2_check_message() still accepts it. The subsequent decoder then reads past the end of the receive buffer. This is reachable during NEGOTIATE and SESSION_SETUP, before the session is established. The resulting out-of-bounds reads are visible under KASAN when mounting against a non-conforming server; both the SPNEGO/negTokenInit and the NTLMSSP challenge decoders are affected: BUG: KASAN: slab-out-of-bounds in asn1_ber_decoder+0x16a7/0x1b00 Read of size 1 at addr ffff8880084d67c0 by task mount.cifs/81 CPU: 1 UID: 0 PID: 81 Comm: mount.cifs Not tainted 7.1.0-rc6 #1 Call Trace: <TASK> dump_stack_lvl+0x4e/0x70 print_report+0x157/0x4c9 kasan_report+0xce/0x100 asn1_ber_decoder+0x16a7/0x1b00 decode_negTokenInit+0x19/0x30 SMB2_negotiate+0x31d9/0x4c90 cifs_negotiate_protocol+0x1f2/0x3f0 cifs_get_smb_ses+0x93f/0x17e0 cifs_mount_get_session+0x7f/0x3a0 cifs_mount+0xb4/0xcf0 cifs_smb3_do_mount+0x23a/0x1500 smb3_get_tree+0x3b0/0x630 vfs_get_tree+0x82/0x2d0 fc_mount+0x10/0x1b0 path_mount+0x50d/0x1de0 __x64_sys_mount+0x20b/0x270 do_syscall_64+0xee/0x590 entry_SYSCALL_64_after_hwframe+0x77/0x7f </TASK> Allocated by task 85: kmem_cache_alloc_noprof+0x106/0x380 mempool_alloc_noprof+0x116/0x1e0 cifs_small_buf_get+0x31/0x80 allocate_buffers+0x10d/0x2b0 cifs_demultiplex_thread+0x1d5/0x1d50 kthread+0x2c6/0x390 ret_from_fork+0x36e/0x5a0 ret_from_fork_asm+0x1a/0x30 The buggy address is located 0 bytes to the right of allocated 448-byte region [ffff8880084d6600, ffff8880084d67c0) which belongs to the cache cifs_small_rq of size 448 BUG: KASAN: slab-out-of-bounds in kmemdup_noprof+0x36/0x50 Read of size 329 at addr ffff88800726c678 by task mount.cifs/89 CPU: 0 UID: 0 PID: 89 Comm: mount.cifs Tainted: G B 7.1.0-rc6 #1 Call Trace: <TASK> dump_stack_lvl+0x4e/0x70 print_report+0x157/0x4c9 kasan_report+0xce/0x100 kasan_check_range+0x10f/0x1e0 __asan_memcpy+0x23/0x60 kmemdup_noprof+0x36/0x50 decode_ntlmssp_challenge+0x457/0x680 SMB2_sess_auth_rawntlmssp_negotiate+0x6f0/0xcb0 SMB2_sess_setup+0x219/0x4f0 cifs_setup_session+0x248/0xaf0 cifs_get_smb_ses+0xf79/0x17e0 cifs_mount_get_session+0x7f/0x3a0 cifs_mount+0xb4/0xcf0 cifs_smb3_do_mount+0x23a/0x1500 smb3_get_tree+0x3b0/0x630 vfs_get_tree+0x82/0x2d0 fc_mount+0x10/0x1b0 path_mount+0x50d/0x1de0 __x64_sys_mount+0x20b/0x270 do_syscall_64+0xee/0x590 entry_SYSCALL_64_after_hwframe+0x77/0x7f </TASK> Allocated by task 93: kmem_cache_alloc_noprof+0x106/0x380 mempool_alloc_noprof+0x116/0x1e0 cifs_small_buf_get+0x31/0x80 allocate_buffers+0x10d/0x2b0 cifs_demultiplex_thread+0x1d5/0x1d50 kthread+0x2c6/0x390 ret_from_fork+0x36e/0x5a0 ret_from_fork_asm+0x1a/0x30 The buggy address is located 120 bytes inside of allocated 448-byte region [ffff88800726c600, ffff88800726c7c0) which belongs to the cache cifs_small_rq of size 448 Restrict the +1 exemption to responses that have no data area, so that it still covers the bcc[0] omission it was meant for. When a data area is present, the +1 discrepancy instead means the reported data length overruns the ---truncated---
References
Impacted products
Vendor Product Version
Linux Linux Version: 093b2bdad3221e3fae3c26d89387e7297a157664
Version: 093b2bdad3221e3fae3c26d89387e7297a157664
Version: 093b2bdad3221e3fae3c26d89387e7297a157664
Version: 093b2bdad3221e3fae3c26d89387e7297a157664
Version: 093b2bdad3221e3fae3c26d89387e7297a157664
Version: 093b2bdad3221e3fae3c26d89387e7297a157664
Version: 093b2bdad3221e3fae3c26d89387e7297a157664
Version: 093b2bdad3221e3fae3c26d89387e7297a157664
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          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nsmb: client: restrict implied bcc[0] exemption to responses without data area\n\nsmb2_check_message() has a long-standing quirk that accepts a response\nwhose calculated length is one byte larger than the bytes actually\nreceived (\"server can return one byte more due to implied bcc[0]\").\nThis was introduced to accommodate servers that omit the trailing bcc[0]\noverlap byte when no data area is present.\n\nHowever, the exemption is applied unconditionally, regardless of whether\nthe command actually carries a data area (has_smb2_data_area[]).  When a\nresponse with a data area is subject to the +1 exemption, the reported\ndata can extend one byte beyond the bytes actually received, yet\nsmb2_check_message() still accepts it.  The subsequent decoder then reads\npast the end of the receive buffer.  This is reachable during NEGOTIATE\nand SESSION_SETUP, before the session is established.\n\nThe resulting out-of-bounds reads are visible under KASAN when mounting\nagainst a non-conforming server; both the SPNEGO/negTokenInit and the\nNTLMSSP challenge decoders are affected:\n\n  BUG: KASAN: slab-out-of-bounds in asn1_ber_decoder+0x16a7/0x1b00\n  Read of size 1 at addr ffff8880084d67c0 by task mount.cifs/81\n  CPU: 1 UID: 0 PID: 81 Comm: mount.cifs Not tainted 7.1.0-rc6 #1\n  Call Trace:\n   \u003cTASK\u003e\n   dump_stack_lvl+0x4e/0x70\n   print_report+0x157/0x4c9\n   kasan_report+0xce/0x100\n   asn1_ber_decoder+0x16a7/0x1b00\n   decode_negTokenInit+0x19/0x30\n   SMB2_negotiate+0x31d9/0x4c90\n   cifs_negotiate_protocol+0x1f2/0x3f0\n   cifs_get_smb_ses+0x93f/0x17e0\n   cifs_mount_get_session+0x7f/0x3a0\n   cifs_mount+0xb4/0xcf0\n   cifs_smb3_do_mount+0x23a/0x1500\n   smb3_get_tree+0x3b0/0x630\n   vfs_get_tree+0x82/0x2d0\n   fc_mount+0x10/0x1b0\n   path_mount+0x50d/0x1de0\n   __x64_sys_mount+0x20b/0x270\n   do_syscall_64+0xee/0x590\n   entry_SYSCALL_64_after_hwframe+0x77/0x7f\n   \u003c/TASK\u003e\n  Allocated by task 85:\n   kmem_cache_alloc_noprof+0x106/0x380\n   mempool_alloc_noprof+0x116/0x1e0\n   cifs_small_buf_get+0x31/0x80\n   allocate_buffers+0x10d/0x2b0\n   cifs_demultiplex_thread+0x1d5/0x1d50\n   kthread+0x2c6/0x390\n   ret_from_fork+0x36e/0x5a0\n   ret_from_fork_asm+0x1a/0x30\n  The buggy address is located 0 bytes to the right of\n   allocated 448-byte region [ffff8880084d6600, ffff8880084d67c0)\n   which belongs to the cache cifs_small_rq of size 448\n\n  BUG: KASAN: slab-out-of-bounds in kmemdup_noprof+0x36/0x50\n  Read of size 329 at addr ffff88800726c678 by task mount.cifs/89\n  CPU: 0 UID: 0 PID: 89 Comm: mount.cifs Tainted: G    B      7.1.0-rc6 #1\n  Call Trace:\n   \u003cTASK\u003e\n   dump_stack_lvl+0x4e/0x70\n   print_report+0x157/0x4c9\n   kasan_report+0xce/0x100\n   kasan_check_range+0x10f/0x1e0\n   __asan_memcpy+0x23/0x60\n   kmemdup_noprof+0x36/0x50\n   decode_ntlmssp_challenge+0x457/0x680\n   SMB2_sess_auth_rawntlmssp_negotiate+0x6f0/0xcb0\n   SMB2_sess_setup+0x219/0x4f0\n   cifs_setup_session+0x248/0xaf0\n   cifs_get_smb_ses+0xf79/0x17e0\n   cifs_mount_get_session+0x7f/0x3a0\n   cifs_mount+0xb4/0xcf0\n   cifs_smb3_do_mount+0x23a/0x1500\n   smb3_get_tree+0x3b0/0x630\n   vfs_get_tree+0x82/0x2d0\n   fc_mount+0x10/0x1b0\n   path_mount+0x50d/0x1de0\n   __x64_sys_mount+0x20b/0x270\n   do_syscall_64+0xee/0x590\n   entry_SYSCALL_64_after_hwframe+0x77/0x7f\n   \u003c/TASK\u003e\n  Allocated by task 93:\n   kmem_cache_alloc_noprof+0x106/0x380\n   mempool_alloc_noprof+0x116/0x1e0\n   cifs_small_buf_get+0x31/0x80\n   allocate_buffers+0x10d/0x2b0\n   cifs_demultiplex_thread+0x1d5/0x1d50\n   kthread+0x2c6/0x390\n   ret_from_fork+0x36e/0x5a0\n   ret_from_fork_asm+0x1a/0x30\n  The buggy address is located 120 bytes inside of\n   allocated 448-byte region [ffff88800726c600, ffff88800726c7c0)\n   which belongs to the cache cifs_small_rq of size 448\n\nRestrict the +1 exemption to responses that have no data area, so that\nit still covers the bcc[0] omission it was meant for.  When a data area\nis present, the +1 discrepancy instead means the reported data length\noverruns the\n---truncated---"
        }
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            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:H",
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              "value": "AV:N - A malicious or compromised SMB server can trigger the flaw through crafted TCP responses, typically over port 445.\nAC:L - The server directly controls the frame length, data offset, and declared data length, so no race or condition outside the attacker\u0027s control is required.\nPR:N - NEGOTIATE and SESSION_SETUP responses are processed before authentication and signature verification, requiring no attacker credentials or local capabilities.\nUI:N - An existing persistent SMB mount automatically renegotiates after a server-induced reconnect, allowing exploitation without contemporaneous user action.\nS:U - The vulnerable SMB decoder and resulting kernel impact remain within the host kernel\u0027s security authority.\nC:L - The discrepancy permits exactly one byte beyond the received data to be read; the NTLM path can preserve and reflect that byte in subsequent authentication data, but the disclosure is strictly bounded.\nI:N - The flaw performs an out-of-bounds read and copies data into valid allocations; it provides no out-of-bounds write or other demonstrated memory-modification primitive.\nA:H - The demonstrated slab out-of-bounds access raises a KASAN BUG and can panic hardened kernels, and a malicious peer can retrigger it during negotiation or reconnection."
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        "dateUpdated": "2026-08-17T04:55:51.813Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
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        {
          "url": "https://git.kernel.org/stable/c/8d0bbc78046d264bbf6a574ea6f9072258a43e35"
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          "url": "https://git.kernel.org/stable/c/b6a381c01e2ac98a48e32ac0f2a45bbadd9e26b0"
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        {
          "url": "https://git.kernel.org/stable/c/53b7c271f06be4dd5cfc8c6ef552a8355c891a7f"
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      "title": "smb: client: restrict implied bcc[0] exemption to responses without data area",
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    "assignerShortName": "Linux",
    "cveId": "CVE-2026-64448",
    "datePublished": "2026-07-25T08:51:18.796Z",
    "dateReserved": "2026-07-19T15:36:31.788Z",
    "dateUpdated": "2026-10-19T20:38:30.137Z",
    "state": "PUBLISHED"
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    "vulnrichment": {
      "containers": "{\"adp\": [{\"title\": \"CISA ADP Vulnrichment\", \"metrics\": [{\"other\": {\"type\": \"ssvc\", \"content\": {\"id\": \"CVE-2026-64448\", \"role\": \"CISA Coordinator\", \"options\": [{\"Exploitation\": \"none\"}, {\"Automatable\": \"yes\"}, {\"Technical Impact\": \"partial\"}], \"version\": \"2.0.3\", \"timestamp\": \"2026-10-16T15:41:01.162608Z\"}}}], \"problemTypes\": [{\"descriptions\": [{\"lang\": \"en\", \"type\": \"CWE\", \"cweId\": \"CWE-125\", \"description\": \"CWE-125 Out-of-bounds Read\"}]}], \"providerMetadata\": {\"orgId\": \"134c704f-9b21-4f2e-91b3-4a467353bcc0\", \"shortName\": \"CISA-ADP\", \"dateUpdated\": \"2026-10-16T15:41:02.783Z\"}}], \"cna\": {\"title\": \"smb: client: restrict implied bcc[0] exemption to responses without data area\", \"metrics\": [{\"cvssV3_1\": {\"version\": \"3.1\", \"baseScore\": 8.2, \"baseSeverity\": \"HIGH\", \"vectorString\": \"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:H\"}, \"scenarios\": [{\"lang\": \"en\", \"value\": \"AV:N - A malicious or compromised SMB server can trigger the flaw through crafted TCP responses, typically over port 445.\\nAC:L - The server directly controls the frame length, data offset, and declared data length, so no race or condition outside the attacker\u0027s control is required.\\nPR:N - NEGOTIATE and SESSION_SETUP responses are processed before authentication and signature verification, requiring no attacker credentials or local capabilities.\\nUI:N - An existing persistent SMB mount automatically renegotiates after a server-induced reconnect, allowing exploitation without contemporaneous user action.\\nS:U - The vulnerable SMB decoder and resulting kernel impact remain within the host kernel\u0027s security authority.\\nC:L - The discrepancy permits exactly one byte beyond the received data to be read; the NTLM path can preserve and reflect that byte in subsequent authentication data, but the disclosure is strictly bounded.\\nI:N - The flaw performs an out-of-bounds read and copies data into valid allocations; it provides no out-of-bounds write or other demonstrated memory-modification primitive.\\nA:H - The demonstrated slab out-of-bounds access raises a KASAN BUG and can panic hardened kernels, and a malicious peer can retrigger it during negotiation or reconnection.\"}]}], \"affected\": [{\"repo\": \"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\", \"vendor\": \"Linux\", \"product\": \"Linux\", \"versions\": [{\"status\": \"affected\", \"version\": \"093b2bdad3221e3fae3c26d89387e7297a157664\", \"lessThan\": \"8d0bbc78046d264bbf6a574ea6f9072258a43e35\", \"versionType\": \"git\"}, {\"status\": \"affected\", \"version\": \"093b2bdad3221e3fae3c26d89387e7297a157664\", \"lessThan\": \"b6a381c01e2ac98a48e32ac0f2a45bbadd9e26b0\", \"versionType\": \"git\"}, {\"status\": \"affected\", \"version\": \"093b2bdad3221e3fae3c26d89387e7297a157664\", \"lessThan\": \"31c6312608c60b72a1feb99a5afb680645a3e8a3\", \"versionType\": \"git\"}, {\"status\": \"affected\", \"version\": \"093b2bdad3221e3fae3c26d89387e7297a157664\", \"lessThan\": \"573e502d14714d2947e22e7eff40ec20a6a44a42\", \"versionType\": \"git\"}, {\"status\": \"affected\", \"version\": \"093b2bdad3221e3fae3c26d89387e7297a157664\", \"lessThan\": \"419ec1b604d7fb60c10aec2dc062371f9fcd4940\", \"versionType\": \"git\"}, {\"status\": \"affected\", \"version\": \"093b2bdad3221e3fae3c26d89387e7297a157664\", \"lessThan\": \"ceb875a375dedbf51c9425c1d13a2d7a8435c08c\", \"versionType\": \"git\"}, {\"status\": \"affected\", \"version\": \"093b2bdad3221e3fae3c26d89387e7297a157664\", \"lessThan\": \"6e9d10f62773b99bd927940fd9cbdfe7207e23ff\", \"versionType\": \"git\"}, {\"status\": \"affected\", \"version\": \"093b2bdad3221e3fae3c26d89387e7297a157664\", \"lessThan\": \"53b7c271f06be4dd5cfc8c6ef552a8355c891a7f\", \"versionType\": \"git\"}], \"programFiles\": [\"fs/smb/client/smb2misc.c\"], \"defaultStatus\": \"unaffected\"}, {\"repo\": \"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\", \"vendor\": \"Linux\", \"product\": \"Linux\", \"versions\": [{\"status\": \"affected\", \"version\": \"3.6\"}, {\"status\": \"unaffected\", \"version\": \"0\", \"lessThan\": \"3.6\", \"versionType\": \"semver\"}, {\"status\": \"unaffected\", \"version\": \"5.10.261\", \"versionType\": \"semver\", \"lessThanOrEqual\": \"5.10.*\"}, {\"status\": \"unaffected\", \"version\": \"5.15.212\", \"versionType\": \"semver\", \"lessThanOrEqual\": \"5.15.*\"}, {\"status\": \"unaffected\", \"version\": \"6.1.178\", \"versionType\": \"semver\", \"lessThanOrEqual\": \"6.1.*\"}, {\"status\": \"unaffected\", \"version\": \"6.6.145\", \"versionType\": \"semver\", \"lessThanOrEqual\": \"6.6.*\"}, {\"status\": \"unaffected\", \"version\": \"6.12.96\", \"versionType\": \"semver\", \"lessThanOrEqual\": \"6.12.*\"}, {\"status\": \"unaffected\", \"version\": \"6.18.39\", \"versionType\": \"semver\", \"lessThanOrEqual\": \"6.18.*\"}, {\"status\": \"unaffected\", \"version\": \"7.1.4\", \"versionType\": \"semver\", \"lessThanOrEqual\": \"7.1.*\"}, {\"status\": \"unaffected\", \"version\": \"7.2\", \"versionType\": \"original_commit_for_fix\", \"lessThanOrEqual\": \"*\"}], \"programFiles\": [\"fs/smb/client/smb2misc.c\"], \"defaultStatus\": \"affected\"}], \"references\": [{\"url\": \"https://git.kernel.org/stable/c/8d0bbc78046d264bbf6a574ea6f9072258a43e35\"}, {\"url\": \"https://git.kernel.org/stable/c/b6a381c01e2ac98a48e32ac0f2a45bbadd9e26b0\"}, {\"url\": \"https://git.kernel.org/stable/c/31c6312608c60b72a1feb99a5afb680645a3e8a3\"}, {\"url\": \"https://git.kernel.org/stable/c/573e502d14714d2947e22e7eff40ec20a6a44a42\"}, {\"url\": \"https://git.kernel.org/stable/c/419ec1b604d7fb60c10aec2dc062371f9fcd4940\"}, {\"url\": \"https://git.kernel.org/stable/c/ceb875a375dedbf51c9425c1d13a2d7a8435c08c\"}, {\"url\": \"https://git.kernel.org/stable/c/6e9d10f62773b99bd927940fd9cbdfe7207e23ff\"}, {\"url\": \"https://git.kernel.org/stable/c/53b7c271f06be4dd5cfc8c6ef552a8355c891a7f\"}], \"x_generator\": {\"engine\": \"bippy-1.2.0\"}, \"descriptions\": [{\"lang\": \"en\", \"value\": \"In the Linux kernel, the following vulnerability has been resolved:\\n\\nsmb: client: restrict implied bcc[0] exemption to responses without data area\\n\\nsmb2_check_message() has a long-standing quirk that accepts a response\\nwhose calculated length is one byte larger than the bytes actually\\nreceived (\\\"server can return one byte more due to implied bcc[0]\\\").\\nThis was introduced to accommodate servers that omit the trailing bcc[0]\\noverlap byte when no data area is present.\\n\\nHowever, the exemption is applied unconditionally, regardless of whether\\nthe command actually carries a data area (has_smb2_data_area[]).  When a\\nresponse with a data area is subject to the +1 exemption, the reported\\ndata can extend one byte beyond the bytes actually received, yet\\nsmb2_check_message() still accepts it.  The subsequent decoder then reads\\npast the end of the receive buffer.  This is reachable during NEGOTIATE\\nand SESSION_SETUP, before the session is established.\\n\\nThe resulting out-of-bounds reads are visible under KASAN when mounting\\nagainst a non-conforming server; both the SPNEGO/negTokenInit and the\\nNTLMSSP challenge decoders are affected:\\n\\n  BUG: KASAN: slab-out-of-bounds in asn1_ber_decoder+0x16a7/0x1b00\\n  Read of size 1 at addr ffff8880084d67c0 by task mount.cifs/81\\n  CPU: 1 UID: 0 PID: 81 Comm: mount.cifs Not tainted 7.1.0-rc6 #1\\n  Call Trace:\\n   \u003cTASK\u003e\\n   dump_stack_lvl+0x4e/0x70\\n   print_report+0x157/0x4c9\\n   kasan_report+0xce/0x100\\n   asn1_ber_decoder+0x16a7/0x1b00\\n   decode_negTokenInit+0x19/0x30\\n   SMB2_negotiate+0x31d9/0x4c90\\n   cifs_negotiate_protocol+0x1f2/0x3f0\\n   cifs_get_smb_ses+0x93f/0x17e0\\n   cifs_mount_get_session+0x7f/0x3a0\\n   cifs_mount+0xb4/0xcf0\\n   cifs_smb3_do_mount+0x23a/0x1500\\n   smb3_get_tree+0x3b0/0x630\\n   vfs_get_tree+0x82/0x2d0\\n   fc_mount+0x10/0x1b0\\n   path_mount+0x50d/0x1de0\\n   __x64_sys_mount+0x20b/0x270\\n   do_syscall_64+0xee/0x590\\n   entry_SYSCALL_64_after_hwframe+0x77/0x7f\\n   \u003c/TASK\u003e\\n  Allocated by task 85:\\n   kmem_cache_alloc_noprof+0x106/0x380\\n   mempool_alloc_noprof+0x116/0x1e0\\n   cifs_small_buf_get+0x31/0x80\\n   allocate_buffers+0x10d/0x2b0\\n   cifs_demultiplex_thread+0x1d5/0x1d50\\n   kthread+0x2c6/0x390\\n   ret_from_fork+0x36e/0x5a0\\n   ret_from_fork_asm+0x1a/0x30\\n  The buggy address is located 0 bytes to the right of\\n   allocated 448-byte region [ffff8880084d6600, ffff8880084d67c0)\\n   which belongs to the cache cifs_small_rq of size 448\\n\\n  BUG: KASAN: slab-out-of-bounds in kmemdup_noprof+0x36/0x50\\n  Read of size 329 at addr ffff88800726c678 by task mount.cifs/89\\n  CPU: 0 UID: 0 PID: 89 Comm: mount.cifs Tainted: G    B      7.1.0-rc6 #1\\n  Call Trace:\\n   \u003cTASK\u003e\\n   dump_stack_lvl+0x4e/0x70\\n   print_report+0x157/0x4c9\\n   kasan_report+0xce/0x100\\n   kasan_check_range+0x10f/0x1e0\\n   __asan_memcpy+0x23/0x60\\n   kmemdup_noprof+0x36/0x50\\n   decode_ntlmssp_challenge+0x457/0x680\\n   SMB2_sess_auth_rawntlmssp_negotiate+0x6f0/0xcb0\\n   SMB2_sess_setup+0x219/0x4f0\\n   cifs_setup_session+0x248/0xaf0\\n   cifs_get_smb_ses+0xf79/0x17e0\\n   cifs_mount_get_session+0x7f/0x3a0\\n   cifs_mount+0xb4/0xcf0\\n   cifs_smb3_do_mount+0x23a/0x1500\\n   smb3_get_tree+0x3b0/0x630\\n   vfs_get_tree+0x82/0x2d0\\n   fc_mount+0x10/0x1b0\\n   path_mount+0x50d/0x1de0\\n   __x64_sys_mount+0x20b/0x270\\n   do_syscall_64+0xee/0x590\\n   entry_SYSCALL_64_after_hwframe+0x77/0x7f\\n   \u003c/TASK\u003e\\n  Allocated by task 93:\\n   kmem_cache_alloc_noprof+0x106/0x380\\n   mempool_alloc_noprof+0x116/0x1e0\\n   cifs_small_buf_get+0x31/0x80\\n   allocate_buffers+0x10d/0x2b0\\n   cifs_demultiplex_thread+0x1d5/0x1d50\\n   kthread+0x2c6/0x390\\n   ret_from_fork+0x36e/0x5a0\\n   ret_from_fork_asm+0x1a/0x30\\n  The buggy address is located 120 bytes inside of\\n   allocated 448-byte region [ffff88800726c600, ffff88800726c7c0)\\n   which belongs to the cache cifs_small_rq of size 448\\n\\nRestrict the +1 exemption to responses that have no data area, so that\\nit still covers the bcc[0] omission it was meant for.  When a data area\\nis present, the +1 discrepancy instead means the reported data length\\noverruns the\\n---truncated---\"}], \"cpeApplicability\": [{\"nodes\": [{\"negate\": false, \"cpeMatch\": [{\"criteria\": \"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\", \"vulnerable\": true, \"versionEndExcluding\": \"5.10.261\", \"versionStartIncluding\": \"3.6\"}, {\"criteria\": \"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\", \"vulnerable\": true, \"versionEndExcluding\": \"5.15.212\", \"versionStartIncluding\": \"3.6\"}, {\"criteria\": \"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\", \"vulnerable\": true, \"versionEndExcluding\": \"6.1.178\", \"versionStartIncluding\": \"3.6\"}, {\"criteria\": \"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\", \"vulnerable\": true, \"versionEndExcluding\": \"6.6.145\", \"versionStartIncluding\": \"3.6\"}, {\"criteria\": \"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\", \"vulnerable\": true, \"versionEndExcluding\": \"6.12.96\", \"versionStartIncluding\": \"3.6\"}, {\"criteria\": \"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\", \"vulnerable\": true, \"versionEndExcluding\": \"6.18.39\", \"versionStartIncluding\": \"3.6\"}, {\"criteria\": \"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\", \"vulnerable\": true, \"versionEndExcluding\": \"7.1.4\", \"versionStartIncluding\": \"3.6\"}, {\"criteria\": \"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*\", \"vulnerable\": true, \"versionEndExcluding\": \"7.2\", \"versionStartIncluding\": \"3.6\"}], \"operator\": \"OR\"}]}], \"providerMetadata\": {\"orgId\": \"416baaa9-dc9f-4396-8d5f-8c081fb06d67\", \"shortName\": \"Linux\", \"dateUpdated\": \"2026-08-17T04:55:51.813Z\"}}}",
      "cveMetadata": "{\"cveId\": \"CVE-2026-64448\", \"state\": \"PUBLISHED\", \"dateUpdated\": \"2026-10-19T20:38:30.137Z\", \"dateReserved\": \"2026-07-19T15:36:31.788Z\", \"assignerOrgId\": \"416baaa9-dc9f-4396-8d5f-8c081fb06d67\", \"datePublished\": \"2026-07-25T08:51:18.796Z\", \"assignerShortName\": \"Linux\"}",
      "dataType": "CVE_RECORD",
      "dataVersion": "5.2"
    }
  }
}


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