In the Linux kernel, the following vulnerability has been resolved: tcp: reject net_iov in zerocopy receive mapping hints After copying a readable prefix, receive_fallback_to_copy() asks tcp_zerocopy_set_hint_for_skb() where page mapping can resume. If the next skb is unreadable, find_next_mappable_frag() passes its net_iov fragment to can_map_frag(). skb_frag_page() returns NULL for a net_iov, but can_map_frag() dereferences it in PageCompound(). A v7.2 KASAN run on a connected TCP socket with 64 readable bytes followed by a 4096-byte NET_IOV_DMABUF fragment reported: BUG: KASAN: null-ptr-deref in can_map_frag tcp_zerocopy_receive -> can_map_frag Kernel panic - not syncing: KASAN: panic_on_warn set The diagnostic inserted the net_iov directly because the test host has no devmem-capable NIC. Hardware end-to-end reachability remains untested and requires CONFIG_NET_DEVMEM plus a supported DMA-buf-bound RX queue. Reject all net_iov fragments before skb_frag_page(). This covers both DMABUF and IOURING net_iov types while leaving page-backed checks unchanged. With the guard, the same queue copied the readable prefix, returned a 4096-byte skip hint, and completed without a fault.

The remote Ubuntu 26.04 LTS host has a package installed that is affected by multiple vulnerabilities as referenced in the USN-9018-1 advisory.

    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:

    - Network file systems library;

    - Stream parser;

    - ARM64 architecture;

    - PowerPC architecture;

    - RISC-V architecture;

    - S390 architecture;

    - User-Mode Linux (UML);

    - x86 architecture;

    - Block layer subsystem;

    - Android drivers;

    - Bluetooth drivers;

    - TPM device driver;

    - DPLL subsystem;

    - EDAC drivers;

    - GPIO subsystem;

    - GPU drivers;

    - HID subsystem;

    - IIO subsystem;

    - IIO ADC drivers;

    - InfiniBand drivers;

    - Input Device (Miscellaneous) drivers;

    - Multiple devices driver;

    - MemoryStick subsystem;

    - MMC subsystem;

    - MTD block device drivers;

    - Network drivers;

    - Ethernet bonding driver;

    - Mellanox network drivers;

    - STMicroelectronics network drivers;

    - Ethernet team driver;

    - MediaTek network drivers;

    - NVME drivers;

    - Device tree and open firmware driver;

    - Power sequencing drivers;

    - Voltage and Current Regulator drivers;

    - Real Time Clock drivers;

    - SCSI subsystem;

    - Greybus lights staging drivers;

    - Trusted Execution Environment drivers;

    - Thunderbolt and USB4 drivers;

    - TTY drivers;

    - Cadence USB3 driver;

    - USB Device Class drivers;

    - USB core drivers;

    - DesignWare USB2 driver;

    - DesignWare USB3 driver;

    - USB Gadget drivers;

    - USB Serial drivers;

    - USB Mass Storage drivers;

    - USB Type-C support driver;

    - USB Type-C Port Controller Manager driver;

    - TI TPS6598x USB Power Delivery controller driver;

    - USB Type-C Connector System Software Interface driver;

    - Amazon Nitro Enclaves driver;

    - Virtual machine generation ID driver;

    - BTRFS file system;

    - File systems infrastructure;

    - SMB network file system;

    - XFS file system;

    - BPF subsystem;

    - io_uring subsystem;

    - Netfilter;

    - Namespaces infrastructure;

    - Networking core;

    - Networking subsytem;

    - Virtio network driver;

    - Bluetooth subsystem;

    - IPv4 networking;

    - Network traffic control;

    - Audit subsystem;

    - Control group (cgroup);

    - Perf events;

    - Kernel fork() syscall;

    - Kernel futex primitives;

    - KProbes tracing;

    - Kexec HandOver (KHO);

    - Kernel module support;

    - Tracing infrastructure;

    - Workqueue subsystem;

    - Memory management;

    - Ethernet bridge;

    - Devlink API;

    - IPv6 networking;

    - MAC80211 subsystem;

    - Management Component Transport Protocol (MCTP);

    - Open vSwitch;

    - Packet sockets;

    - SCTP protocol;

    - SMC sockets;

    - TIPC protocol;

    - VMware vSockets driver;

    - Wireless networking;

    - XFRM subsystem;

    - Drivers core;

    - Key management;

    - SELinux security module;

    - ALSA framework;

    - Creative Sound Blaster X-Fi driver;

    - Analog Devices audio codecs;

    - Maxim audio codecs;

    - Realtek audio codecs;

    - QCOM ASoC drivers;

    - Samsung ASoC drivers;

    - SoundWire (SDCA) ASoC drivers;

    - USB sound devices; (CVE-2026-68305, CVE-2026-72404, CVE-2026-72497, CVE-2026-74527, CVE-2026-74568,     CVE-2026-89568, CVE-2026-89764, CVE-2026-89907, CVE-2026-90144, CVE-2026-90155, CVE-2026-90162,     CVE-2026-90167, CVE-2026-90317, CVE-2026-93175, CVE-2026-98038, CVE-2026-98375, CVE-2026-98432,     CVE-2026-98655, CVE-2026-98656, CVE-2026-98657, CVE-2026-98658, CVE-2026-98659, CVE-2026-98660,     CVE-2026-98661, CVE-2026-98662, CVE-2026-98663, CVE-2026-98664, CVE-2026-98665, CVE-2026-98666,     CVE-2026-98667, CVE-2026-98668, CVE-2026-98669, CVE-2026-98670, CVE-2026-98671, CVE-2026-98672,     CVE-2026-98673, CVE-2026-98674, CVE-2026-98675, CVE-2026-98676, CVE-2026-98677, CVE-2026-98678,     CVE-2026-98679, CVE-2026-98680, CVE-2026-98681, CVE-2026-98682, CVE-2026-98683, CVE-2026-98684,     CVE-2026-98685, CVE-2026-98686, CVE-2026-98687, CVE-2026-98689, CVE-2026-98690, CVE-2026-98691,     CVE-2026-98692, CVE-2026-98693, CVE-2026-98694, CVE-2026-98695, CVE-2026-98696, CVE-2026-98697,     CVE-2026-98698, CVE-2026-98699, CVE-2026-98700, CVE-2026-98701, CVE-2026-98702, CVE-2026-98703,     CVE-2026-98704, CVE-2026-98705, CVE-2026-98706, CVE-2026-98707, CVE-2026-98708, CVE-2026-98709,     CVE-2026-98710, CVE-2026-98711, CVE-2026-98712, CVE-2026-98713, CVE-2026-98714, CVE-2026-98715,     CVE-2026-98716, CVE-2026-98717, CVE-2026-98718, CVE-2026-98719, CVE-2026-98720, CVE-2026-98721,     CVE-2026-98722, CVE-2026-98723, CVE-2026-98724, CVE-2026-98725, CVE-2026-98726, CVE-2026-98727,     CVE-2026-98728, CVE-2026-98729, CVE-2026-98730, CVE-2026-98731, CVE-2026-98732, CVE-2026-98733,     CVE-2026-98734, CVE-2026-98735, CVE-2026-98736, CVE-2026-98737, CVE-2026-98738, CVE-2026-98739,     CVE-2026-98740, CVE-2026-98741, CVE-2026-98742, CVE-2026-98743, CVE-2026-98744, CVE-2026-98745,     CVE-2026-98746, CVE-2026-98747, CVE-2026-98748, CVE-2026-98749, CVE-2026-98750, CVE-2026-98751,     CVE-2026-98752, CVE-2026-98753, CVE-2026-98754, CVE-2026-98755, CVE-2026-98756, CVE-2026-98757,     CVE-2026-98758, CVE-2026-98759, CVE-2026-98760, CVE-2026-98761, CVE-2026-98762, CVE-2026-98763,     CVE-2026-98764, CVE-2026-98765, CVE-2026-98766, CVE-2026-98767, CVE-2026-98768, CVE-2026-98769,     CVE-2026-98770, CVE-2026-98771, CVE-2026-98772, CVE-2026-98773, CVE-2026-98774, CVE-2026-98775,     CVE-2026-98776, CVE-2026-98777, CVE-2026-98778, CVE-2026-98779, CVE-2026-98780, CVE-2026-98781,     CVE-2026-98782, CVE-2026-98783, CVE-2026-98784, CVE-2026-98785, CVE-2026-98786, CVE-2026-98788,     CVE-2026-98789, CVE-2026-98790, CVE-2026-98791, CVE-2026-98792, CVE-2026-98793, CVE-2026-98794,     CVE-2026-98795, CVE-2026-98796, CVE-2026-98797, CVE-2026-98798, CVE-2026-98799, CVE-2026-98800,     CVE-2026-98801, CVE-2026-98802, CVE-2026-98803, CVE-2026-98804, CVE-2026-98805, CVE-2026-98806,     CVE-2026-98807, CVE-2026-98808, CVE-2026-98809, CVE-2026-98810, CVE-2026-98811, CVE-2026-98812,     CVE-2026-98813, CVE-2026-98814, CVE-2026-98816, CVE-2026-98817, CVE-2026-98818, CVE-2026-98819,     CVE-2026-98820, CVE-2026-98821, CVE-2026-98822, CVE-2026-98823, CVE-2026-98824, CVE-2026-98825,     CVE-2026-98826, CVE-2026-98827, CVE-2026-98828, CVE-2026-98829, CVE-2026-98830, CVE-2026-98831,     CVE-2026-98833, CVE-2026-98834, CVE-2026-98835, CVE-2026-98836, CVE-2026-98837, CVE-2026-98838,     CVE-2026-98839, CVE-2026-98840, CVE-2026-98841, CVE-2026-98842, CVE-2026-98843, CVE-2026-98844,     CVE-2026-98845, CVE-2026-98846, CVE-2026-98847, CVE-2026-98848, CVE-2026-98849, CVE-2026-98850,     CVE-2026-98851, CVE-2026-98852, CVE-2026-98853, CVE-2026-98854, CVE-2026-98855, CVE-2026-98856,     CVE-2026-98857, CVE-2026-98858, CVE-2026-98859, CVE-2026-98860, CVE-2026-98861, CVE-2026-98862,     CVE-2026-98863, CVE-2026-98931, CVE-2026-98932, CVE-2026-98933, CVE-2026-98934, CVE-2026-98935,     CVE-2026-98936, CVE-2026-98937, CVE-2026-98939, CVE-2026-98940, CVE-2026-98944, CVE-2026-98945,     CVE-2026-98946, CVE-2026-98947, CVE-2026-98948, CVE-2026-98949, CVE-2026-98950, CVE-2026-98951,     CVE-2026-98952, CVE-2026-98953, CVE-2026-98954, CVE-2026-98955, CVE-2026-98956, CVE-2026-98957,     CVE-2026-98958, CVE-2026-98959, CVE-2026-98960, CVE-2026-98961, CVE-2026-98962, CVE-2026-98963,     CVE-2026-98964, CVE-2026-98965, CVE-2026-98966, CVE-2026-98967, CVE-2026-98968, CVE-2026-98969,     CVE-2026-98970, CVE-2026-98971, CVE-2026-98972, CVE-2026-98973, CVE-2026-98974, CVE-2026-98975,     CVE-2026-98977, CVE-2026-98978, CVE-2026-98979, CVE-2026-98980, CVE-2026-98981, CVE-2026-98982,     CVE-2026-98983, CVE-2026-98984, CVE-2026-98985, CVE-2026-98986, CVE-2026-98987, CVE-2026-98988,     CVE-2026-98989, CVE-2026-98990, CVE-2026-98991, CVE-2026-98992, CVE-2026-98993, CVE-2026-98994,     CVE-2026-98995, CVE-2026-98996, CVE-2026-98997, CVE-2026-98999, CVE-2026-99000, CVE-2026-99001,     CVE-2026-99002, CVE-2026-99003, CVE-2026-99004, CVE-2026-99005, CVE-2026-99006, CVE-2026-99007,     CVE-2026-99008, CVE-2026-99009, CVE-2026-99010, CVE-2026-99011, CVE-2026-99012, CVE-2026-99013,     CVE-2026-99014, CVE-2026-99015, CVE-2026-99016, CVE-2026-99017, CVE-2026-99018, CVE-2026-99019,     CVE-2026-99020, CVE-2026-99021, CVE-2026-99022, CVE-2026-99023, CVE-2026-99024, CVE-2026-99025,     CVE-2026-99026, CVE-2026-99027, CVE-2026-99028, CVE-2026-99029, CVE-2026-99030, CVE-2026-99031,     CVE-2026-99032, CVE-2026-99033, CVE-2026-99034, CVE-2026-99035, CVE-2026-99036, CVE-2026-99037,     CVE-2026-99038, CVE-2026-99039, CVE-2026-99040, CVE-2026-99041, CVE-2026-99043, CVE-2026-99044,     CVE-2026-99045, CVE-2026-99046, CVE-2026-99047, CVE-2026-99048, CVE-2026-99049, CVE-2026-99050,     CVE-2026-99051, CVE-2026-99052, CVE-2026-99053, CVE-2026-99054, CVE-2026-99055, CVE-2026-99056,     CVE-2026-99057, CVE-2026-99058, CVE-2026-99059, CVE-2026-99060, CVE-2026-99061, CVE-2026-99062,     CVE-2026-99063, CVE-2026-99064, CVE-2026-99065, CVE-2026-99066, CVE-2026-99067, CVE-2026-99068,     CVE-2026-99069, CVE-2026-99070, CVE-2026-99071, CVE-2026-99072, CVE-2026-99073, CVE-2026-99074,     CVE-2026-99075, CVE-2026-99076, CVE-2026-99077, CVE-2026-99078, CVE-2026-99079, CVE-2026-99080,     CVE-2026-99081, CVE-2026-99088, CVE-2026-99089, CVE-2026-99090, CVE-2026-99091, CVE-2026-99092,     CVE-2026-99093, CVE-2026-99094, CVE-2026-99095, CVE-2026-99096, CVE-2026-99097, CVE-2026-99098,     CVE-2026-99099, CVE-2026-99999)

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.

An update of the linux package has been released.

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

  - In the Linux kernel, the following vulnerability has been resolved: tcp: reject net_iov in zerocopy     receive mapping hints After copying a readable prefix, receive_fallback_to_copy() asks     tcp_zerocopy_set_hint_for_skb() where page mapping can resume. If the next skb is unreadable,     find_next_mappable_frag() passes its net_iov fragment to can_map_frag(). skb_frag_page() returns NULL for     a net_iov, but can_map_frag() dereferences it in PageCompound(). A v7.2 KASAN run on a connected TCP     socket with 64 readable bytes followed by a 4096-byte NET_IOV_DMABUF fragment reported: BUG: KASAN: null-     ptr-deref in can_map_frag tcp_zerocopy_receive -> can_map_frag Kernel panic - not syncing: KASAN:
    panic_on_warn set The diagnostic inserted the net_iov directly because the test host has no devmem-capable     NIC. Hardware end-to-end reachability remains untested and requires CONFIG_NET_DEVMEM plus a supported     DMA-buf-bound RX queue. Reject all net_iov fragments before skb_frag_page(). This covers both DMABUF and     IOURING net_iov types while leaving page-backed checks unchanged. With the guard, the same queue copied     the readable prefix, returned a 4096-byte skip hint, and completed without a fault. (CVE-2026-99055)

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

ID	Name	Product	Family	Type	Severity
381339	Ubuntu 26.04 LTS : Linux kernel vulnerabilities (USN-9018-1)	Nessus	Ubuntu Local Security Checks	Local	critical
375086	Photon OS 5.0: Linux PHSA-2026-5.0-92-1044	Nessus	PhotonOS Local Security Checks	Local	critical
373466	Amazon Linux 2023 : bpftool6.12, kernel6.12, kernel6.12-devel (ALAS2023-2026-3335)	Nessus	Amazon Linux Local Security Checks	Local	medium
372339	Linux Distros Unpatched Vulnerability : CVE-2026-99055	Nessus	Misc.	Local	medium

Detections

Analytics

CVE-2026-99055

high

Tenable Plugins

critical

critical

medium

medium