In the Linux kernel, the following vulnerability has been resolved: ksmbd: fix use-after-free of conn->preauth_info in concurrent SMB2 NEGOTIATE conn->preauth_info is shared connection state (struct preauth_integrity_info, kmalloc-96) that is allocated and freed by the SMB2 NEGOTIATE handler and read by the response send path. smb2_handle_negotiate() allocates conn->preauth_info, and on a deassemble_neg_contexts() failure kfrees it and sets it to NULL. Both the allocation and the free/NULL happen under ksmbd_conn_lock(conn) (the connection srv_mutex), which is held across the whole handler body. The response send path smb3_preauth_hash_rsp(), called from the send: block of __handle_ksmbd_work(), reads conn->preauth_info and dereferences conn->preauth_info->Preauth_HashValue (via ksmbd_gen_preauth_integrity_hash()) without taking conn_lock. When a client drives two SMB2 NEGOTIATE requests on the same connection, one worker can free conn->preauth_info on the failing-negotiate path while a concurrent send-path worker is reading it, producing a slab use-after-free read (KASAN-confirmed). The send-path read tested conn->preauth_info for NULL but raced with the free that occurs between the NULL check and the dereference, so the NULL guard alone does not close the window. Serialize the NEGOTIATE-branch read in smb3_preauth_hash_rsp() under ksmbd_conn_lock(conn) and re-check conn->preauth_info inside the lock. Because the negotiate handler holds conn_lock across its kfree + NULL assignment, a reader that also takes conn_lock either runs fully before the allocation or fully after the NULL store, and can never observe the freed-but-not-yet-NULLed pointer. ksmbd_gen_preauth_integrity_hash() takes no locks itself (it only computes a SHA-512 over the buffer), so no lock-ordering inversion is introduced, and conn_lock is a sleepable mutex which is safe on this send path (it already performs network I/O).

The remote Ubuntu 24.04 LTS / Pro Realtime 24.04 LTS host has a package installed that is affected by multiple vulnerabilities as referenced in the USN-8781-1 advisory.

    It was discovered that some Arm processors could complete a broadcast translation lookaside buffer (TLB)     invalidation before memory writes made through the invalidated translation were globally observed. A local     attacker could possibly use this to write to memory after permission to do so had been revoked, bypassing     memory protections or escalating privileges. (CVE-2025-10263)

    Several security issues were discovered in the Linux kernel. An attacker could possibly use these to     compromise the system. This update corrects flaws in the following subsystems:

    - ARM64 architecture;

    - User-space API (UAPI);

    - Kernel build system;

    - ARM32 architecture;

    - PowerPC architecture;

    - RISC-V architecture;

    - S390 architecture;

    - User-Mode Linux (UML);

    - x86 architecture;

    - Cryptographic API;

    - Intel NPU Driver;

    - Compute Acceleration Framework;

    - ACPI drivers;

    - Drivers core;

    - DRBD Distributed Replicated Block Device drivers;

    - Rados block device (RBD) driver;

    - Ublk userspace block driver;

    - Compressed RAM block device driver;

    - Bluetooth drivers;

    - Hardware crypto device drivers;

    - CXL (Compute Express Link) drivers;

    - Arm Firmware Framework for ARMv8-A(FFA);

    - EFI core;

    - FPGA Framework;

    - GPU drivers;

    - HID subsystem;

    - Hardware monitoring drivers;

    - I2C subsystem;

    - I3C subsystem;

    - InfiniBand drivers;

    - Input Device core drivers;

    - Input Device (Mouse) drivers;

    - IOMMU subsystem;

    - Multiple devices driver;

    - Media drivers;

    - Fastrpc Driver;

    - Network drivers;

    - Mellanox network drivers;

    - Microsoft Azure Network Adapter (MANA) driver;

    - MediaTek network drivers;

    - NVME drivers;

    - Operating Performance Points (OPP) driver;

    - PCI subsystem;

    - PTP clock framework;

    - RPMSG subsystem;

    - SCSI subsystem;

    - SoundWire subsystem;

    - SPI subsystem;

    - Greybus lights staging drivers;

    - Media staging drivers;

    - NVIDIA Tegra embedded controller (NVEC) staging driver;

    - Realtek RTL8723BS SDIO drivers;

    - TCM subsystem;

    - Trusted Execution Environment drivers;

    - Thunderbolt and USB4 drivers;

    - TTY drivers;

    - USB Gadget drivers;

    - USB Dual Role (OTG-ready) Controller drivers;

    - USB Serial drivers;

    - vDPA drivers;

    - VFIO drivers;

    - Virtio Host (VHOST) subsystem;

    - Virtio drivers;

    - Xen hypervisor drivers;

    - 9P distributed file system;

    - AFS file system;

    - File systems infrastructure;

    - BTRFS file system;

    - Ceph distributed file system;

    - exFAT file system;

    - F2FS file system;

    - GFS2 file system;

    - HFS file system;

    - HFS+ file system;

    - JFS file system;

    - Network file systems library;

    - Network file system (NFS) client;

    - Network file system (NFS) server daemon;

    - NTFS3 file system;

    - OCFS2 file system;

    - OrangeFS file system;

    - SMB network file system;

    - BPF subsystem;

    - File system encryption (fscrypt);

    - Software nodes and device properties;

    - IPv4 networking;

    - KVM subsystem;

    - Mellanox drivers;

    - Memory management;

    - Networking core;

    - Netfilter;

    - Socket messages infrastructure;

    - MediaTek SoC drivers;

    - Sun RPC protocol;

    - Network traffic control;

    - IPv6 networking;

    - Amateur Radio drivers;

    - Bluetooth subsystem;

    - IP tunnels definitions;

    - KCM (Kernel Connection Multiplexor) sockets driver;

    - MultiProtocol Label Switching driver;

    - TCP network protocol;

    - XFRM subsystem;

    - Tracing infrastructure;

    - io_uring subsystem;

    - Control group (cgroup);

    - Perf events;

    - IRQ subsystem;

    - Locking primitives;

    - KProbes tracing;

    - 9P file system network protocol;

    - B.A.T.M.A.N. meshing protocol;

    - Ethernet bridge;

    - CAN network layer;

    - Ceph Core library;

    - Handshake API;

    - HSR network protocol;

    - IFE protocol;

    - L2TP protocol;

    - MAC80211 subsystem;

    - IEEE 802.15.4 subsystem;

    - Multipath TCP;

    - NFC subsystem;

    - Open vSwitch;

    - Phonet protocol;

    - RDS protocol;

    - RxRPC session sockets;

    - SCTP protocol;

    - SMC sockets;

    - TIPC protocol;

    - TLS protocol;

    - Unix domain sockets;

    - VMware vSockets driver;

    - Wireless networking;

    - X.25 network layer;

    - eXpress Data Path;

    - Rust bindings mechanism;

    - AppArmor security module;

    - Key management;

    - Linux Security Modules (LSM) Framework;

    - SELinux security module;

    - ALSA framework;

    - AudioScience HPI driver;

    - Intel ASoC drivers;

    - USB sound devices; (CVE-2024-14040, CVE-2024-35948, CVE-2024-41008, CVE-2024-43872, CVE-2024-44932,     CVE-2024-44964, CVE-2024-49932, CVE-2024-49940, CVE-2024-50106, CVE-2024-50217, CVE-2024-52560,     CVE-2024-53098, CVE-2024-56552, CVE-2024-56591, CVE-2024-57857, CVE-2024-58089, CVE-2024-58094,     CVE-2024-58098, CVE-2024-58100, CVE-2024-58241, CVE-2025-21687, CVE-2025-21693, CVE-2025-21984,     CVE-2025-21985, CVE-2025-22104, CVE-2025-22108, CVE-2025-22109, CVE-2025-23132, CVE-2025-37776,     CVE-2025-37876, CVE-2025-37906, CVE-2025-38064, CVE-2025-38069, CVE-2025-38187, CVE-2025-38204,     CVE-2025-38206, CVE-2025-38242, CVE-2025-38498, CVE-2025-38563, CVE-2025-38565, CVE-2025-38636,     CVE-2025-38717, CVE-2025-39677, CVE-2025-39789, CVE-2025-39859, CVE-2025-39862, CVE-2025-39896,     CVE-2025-39933, CVE-2025-39958, CVE-2025-39990, CVE-2025-40025, CVE-2025-40040, CVE-2025-40054,     CVE-2025-40064, CVE-2025-40074, CVE-2025-40075, CVE-2025-40139, CVE-2025-40158, CVE-2025-40168,     CVE-2025-40170, CVE-2025-40203, CVE-2025-40274, CVE-2025-40344, CVE-2025-40354, CVE-2025-68174,     CVE-2025-68304, CVE-2025-68360, CVE-2025-68745, CVE-2025-68822, CVE-2025-71073, CVE-2025-71074,     CVE-2025-71202, CVE-2025-71289, CVE-2026-23208, CVE-2026-23239, CVE-2026-23240, CVE-2026-23327,     CVE-2026-23393, CVE-2026-23469, CVE-2026-31420, CVE-2026-31479, CVE-2026-31486, CVE-2026-31493,     CVE-2026-31560, CVE-2026-31568, CVE-2026-31630, CVE-2026-31663, CVE-2026-31771, CVE-2026-43009,     CVE-2026-43029, CVE-2026-43042, CVE-2026-43048, CVE-2026-43101, CVE-2026-43116, CVE-2026-43126,     CVE-2026-43172, CVE-2026-43213, CVE-2026-43263, CVE-2026-43303, CVE-2026-43352, CVE-2026-43353,     CVE-2026-43464, CVE-2026-45850, CVE-2026-45894, CVE-2026-45932, CVE-2026-45944, CVE-2026-46054,     CVE-2026-46130, CVE-2026-46158, CVE-2026-46170, CVE-2026-46175, CVE-2026-46181, CVE-2026-46203,     CVE-2026-46275, CVE-2026-46315, CVE-2026-46320, CVE-2026-46324, CVE-2026-46330, CVE-2026-52908,     CVE-2026-52909, CVE-2026-52910, CVE-2026-52912, CVE-2026-52915, CVE-2026-52916, CVE-2026-52918,     CVE-2026-52919, CVE-2026-52921, CVE-2026-52922, CVE-2026-52926, CVE-2026-52934, CVE-2026-52941,     CVE-2026-52956, CVE-2026-52988, CVE-2026-52991, CVE-2026-53000, CVE-2026-53005, CVE-2026-53009,     CVE-2026-53024, CVE-2026-53025, CVE-2026-53053, CVE-2026-53070, CVE-2026-53078, CVE-2026-53089,     CVE-2026-53090, CVE-2026-53091, CVE-2026-53109, CVE-2026-53118, CVE-2026-53120, CVE-2026-53129,     CVE-2026-53131, CVE-2026-53132, CVE-2026-53133, CVE-2026-53148, CVE-2026-53159, CVE-2026-53182,     CVE-2026-53183, CVE-2026-53185, CVE-2026-53186, CVE-2026-53196, CVE-2026-53198, CVE-2026-53216,     CVE-2026-53217, CVE-2026-53221, CVE-2026-53230, CVE-2026-53232, CVE-2026-53239, CVE-2026-53250,     CVE-2026-53254, CVE-2026-53256, CVE-2026-53262, CVE-2026-53264, CVE-2026-53266, CVE-2026-53269,     CVE-2026-53270, CVE-2026-53273, CVE-2026-53275, CVE-2026-53281, CVE-2026-53284, CVE-2026-53354,     CVE-2026-53355, CVE-2026-53357, CVE-2026-53358, CVE-2026-53361, CVE-2026-53368, CVE-2026-53384,     CVE-2026-53398, CVE-2026-53399, CVE-2026-63795, CVE-2026-63796, CVE-2026-63797, CVE-2026-63800,     CVE-2026-63801, CVE-2026-63804, CVE-2026-63807, CVE-2026-63808, CVE-2026-63815, CVE-2026-63818,     CVE-2026-63825, CVE-2026-63828, CVE-2026-63829, CVE-2026-63830, CVE-2026-63831, CVE-2026-63853,     CVE-2026-63858, CVE-2026-63886, CVE-2026-63887, CVE-2026-63888, CVE-2026-63893, CVE-2026-63906,     CVE-2026-63912, CVE-2026-63914, CVE-2026-63915, CVE-2026-63916, CVE-2026-63917, CVE-2026-63919,     CVE-2026-63921, CVE-2026-63922, CVE-2026-63924, CVE-2026-63926, CVE-2026-63940, CVE-2026-63944,     CVE-2026-63945, CVE-2026-63946, CVE-2026-63947, CVE-2026-63948, CVE-2026-63952, CVE-2026-63974,     CVE-2026-63975, CVE-2026-63976, CVE-2026-63978, CVE-2026-63979, CVE-2026-63980, CVE-2026-63984,     CVE-2026-63992, CVE-2026-63993, CVE-2026-63994, CVE-2026-64000, CVE-2026-64007, CVE-2026-64010,     CVE-2026-64011, CVE-2026-64015, CVE-2026-64018, CVE-2026-64025, CVE-2026-64029, CVE-2026-64032,     CVE-2026-64033, CVE-2026-64034, CVE-2026-64039, CVE-2026-64046, CVE-2026-64047, CVE-2026-64048,     CVE-2026-64051, CVE-2026-64055, CVE-2026-64056, CVE-2026-64064, CVE-2026-64073, CVE-2026-64076,     CVE-2026-64077, CVE-2026-64082, CVE-2026-64083, CVE-2026-64084, CVE-2026-64085, CVE-2026-64086,     CVE-2026-64087, CVE-2026-64088, CVE-2026-64089, CVE-2026-64091, CVE-2026-64092, CVE-2026-64093,     CVE-2026-64096, CVE-2026-64097, CVE-2026-64098, CVE-2026-64099, CVE-2026-64102, CVE-2026-64103,     CVE-2026-64106, CVE-2026-64108, CVE-2026-64109, CVE-2026-64111, CVE-2026-64112, CVE-2026-64113,     CVE-2026-64114, CVE-2026-64115, CVE-2026-64116, CVE-2026-64117, CVE-2026-64118, CVE-2026-64121,     CVE-2026-64125, CVE-2026-64126, CVE-2026-64127, CVE-2026-64128, CVE-2026-64133, CVE-2026-64134,     CVE-2026-64135, CVE-2026-64136, CVE-2026-64137, CVE-2026-64138, CVE-2026-64144, CVE-2026-64147,     CVE-2026-64148, CVE-2026-64153, CVE-2026-64155, CVE-2026-64160, CVE-2026-64163, CVE-2026-64165,     CVE-2026-64166, CVE-2026-64168, CVE-2026-64170, CVE-2026-64173, CVE-2026-64174, CVE-2026-64177,     CVE-2026-64178, CVE-2026-64179, CVE-2026-64180, CVE-2026-64182, CVE-2026-64183, CVE-2026-64184,     CVE-2026-64185, CVE-2026-64191, CVE-2026-64206, CVE-2026-64214, CVE-2026-64217, CVE-2026-64218,     CVE-2026-64219, CVE-2026-64220, CVE-2026-64221, CVE-2026-64225, CVE-2026-64231, CVE-2026-64237,     CVE-2026-64247, CVE-2026-64249, CVE-2026-64268, CVE-2026-64269, CVE-2026-64280, CVE-2026-64303,     CVE-2026-64313, CVE-2026-64315, CVE-2026-64319, CVE-2026-64320, CVE-2026-64355, CVE-2026-64361,     CVE-2026-64364, CVE-2026-64382, CVE-2026-64383, CVE-2026-64384, CVE-2026-64385, CVE-2026-64386,     CVE-2026-64387, CVE-2026-64390, CVE-2026-64391, CVE-2026-64392, CVE-2026-64393, CVE-2026-64394,     CVE-2026-64396, CVE-2026-64397, CVE-2026-64399, CVE-2026-64400, CVE-2026-64408, CVE-2026-64438,     CVE-2026-64441, CVE-2026-64445, CVE-2026-64450, CVE-2026-64475, CVE-2026-64510, CVE-2026-64518,     CVE-2026-64523, CVE-2026-64529, CVE-2026-64530, CVE-2026-64534, CVE-2026-64535, CVE-2026-64541,     CVE-2026-64548, CVE-2026-64551, CVE-2026-64552, CVE-2026-64554, CVE-2026-64555, CVE-2026-64557,     CVE-2026-64561, CVE-2026-64562, CVE-2026-64564, CVE-2026-64586, CVE-2026-64597, CVE-2026-64598,     CVE-2026-68082, CVE-2026-68083, CVE-2026-68117, CVE-2026-68123, CVE-2026-68124, CVE-2026-68127,     CVE-2026-68136, CVE-2026-68137, CVE-2026-68138, CVE-2026-68144, CVE-2026-68147, CVE-2026-68152,     CVE-2026-68154, CVE-2026-68156, CVE-2026-68158, CVE-2026-68159, CVE-2026-68160, CVE-2026-68161,     CVE-2026-68162, CVE-2026-68198, CVE-2026-68206, CVE-2026-68209, CVE-2026-68210, CVE-2026-68213,     CVE-2026-68228, CVE-2026-68229, CVE-2026-68300, CVE-2026-68302, CVE-2026-68343, CVE-2026-68381,     CVE-2026-68388, CVE-2026-68426, CVE-2026-68431, CVE-2026-68457, CVE-2026-68461, CVE-2026-68470,     CVE-2026-68476, CVE-2026-68477, CVE-2026-72014, CVE-2026-72020, CVE-2026-72033, CVE-2026-72041,     CVE-2026-72065, CVE-2026-72069, CVE-2026-72071, CVE-2026-72083, CVE-2026-72084, CVE-2026-72085,     CVE-2026-72098, CVE-2026-72111, CVE-2026-72124, CVE-2026-72125, CVE-2026-72126, CVE-2026-72129,     CVE-2026-72130, CVE-2026-72191, CVE-2026-72192, CVE-2026-72194, CVE-2026-72200, CVE-2026-72217,     CVE-2026-72221, CVE-2026-72222, CVE-2026-72226, CVE-2026-72234, CVE-2026-72251, CVE-2026-72255,     CVE-2026-72288, CVE-2026-72289, CVE-2026-72296, CVE-2026-72299, CVE-2026-72317, CVE-2026-72318,     CVE-2026-72319, CVE-2026-72320, CVE-2026-72322, CVE-2026-72323, CVE-2026-72329, CVE-2026-72339,     CVE-2026-72348, CVE-2026-72351, CVE-2026-72380, CVE-2026-72383, CVE-2026-72398, CVE-2026-72399,     CVE-2026-72421, CVE-2026-72422, CVE-2026-72434, CVE-2026-72436, CVE-2026-72451, CVE-2026-72454,     CVE-2026-72466, CVE-2026-72472, CVE-2026-72473, CVE-2026-72487, CVE-2026-72488, CVE-2026-72489,     CVE-2026-72491, CVE-2026-72494, CVE-2026-72495, CVE-2026-72496, CVE-2026-72499, CVE-2026-74255,     CVE-2026-74264, CVE-2026-74267, CVE-2026-74268, CVE-2026-74269, CVE-2026-74279, CVE-2026-74280,     CVE-2026-74287, CVE-2026-74302, CVE-2026-74305, CVE-2026-74310, CVE-2026-74345, CVE-2026-74350,     CVE-2026-74376, CVE-2026-74384, CVE-2026-74394, CVE-2026-74398, CVE-2026-74401, CVE-2026-74405,     CVE-2026-74406, CVE-2026-74407, CVE-2026-74408, CVE-2026-74410, CVE-2026-74411, CVE-2026-74417,     CVE-2026-74427, CVE-2026-74436, CVE-2026-74439, CVE-2026-74440, CVE-2026-74473, CVE-2026-74474,     CVE-2026-74475, CVE-2026-74476, CVE-2026-74478, CVE-2026-74480, CVE-2026-74493, CVE-2026-74495,     CVE-2026-74521, CVE-2026-74538, CVE-2026-74541, CVE-2026-74556, CVE-2026-74569)

Tenable has extracted the preceding description block directly from the Ubuntu security advisory.

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

The Linux/Unix host has one or more packages installed that are impacted by a vulnerability without a vendor supplied patch available.

  - ksmbd: fix use-after-free of conn->preauth_info in concurrent SMB2 NEGOTIATE conn->preauth_info is shared     connection state (struct preauth_integrity_info, kmalloc-96) that is allocated and freed by the SMB2     NEGOTIATE handler and read by the response send path. smb2_handle_negotiate() allocates     conn->preauth_info, and on a deassemble_neg_contexts() failure kfrees it and sets it to NULL. Both the     allocation and the free/NULL happen under ksmbd_conn_lock(conn) (the connection srv_mutex), which is held     across the whole handler body. The response send path smb3_preauth_hash_rsp(), called from the send: block     of __handle_ksmbd_work(), reads conn->preauth_info and dereferences conn->preauth_info->Preauth_HashValue     (via ksmbd_gen_preauth_integrity_hash()) without taking conn_lock. When a client drives two SMB2 NEGOTIATE     requests on the same connection, one worker can free conn->preauth_info on the failing-negotiate path     while a concurrent send-path worker is reading it, producing a slab use-after-free read (KASAN-confirmed).
    The send-path read tested conn->preauth_info for NULL but raced with the free that occurs between the NULL     check and the dereference, so the NULL guard alone does not close the window. Serialize the NEGOTIATE-     branch read in smb3_preauth_hash_rsp() under ksmbd_conn_lock(conn) and re-check conn->preauth_info inside     the lock. Because the negotiate handler holds conn_lock across its kfree + NULL assignment, a reader that     also takes conn_lock either runs fully before the allocation or fully after the NULL store, and can never     observe the freed-but-not-yet-NULLed pointer. ksmbd_gen_preauth_integrity_hash() takes no locks itself (it     only computes a SHA-512 over the buffer), so no lock-ordering inversion is introduced, and conn_lock is a     sleepable mutex which is safe on this send path (it already performs network I/O). (CVE-2026-72422)

Note that Nessus relies on the presence of the package as reported by the vendor.

An update of the linux package has been released.

ID	Name	Product	Family	Type	Severity
348386	Ubuntu 24.04 LTS / Pro Realtime 24.04 LTS : Linux kernel (NVIDIA Tegra) vulnerabilities (USN-8781-1)	Nessus	Ubuntu Local Security Checks	Local	high
337499	Linux Distros Unpatched Vulnerability : CVE-2026-72422	Nessus	Misc.	Local	critical
334784	Photon OS 5.0: Linux PHSA-2026-5.0-92-0952	Nessus	PhotonOS Local Security Checks	Local	high

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Analytics

CVE-2026-72422

critical

Tenable Plugins

high

critical

high