In the Linux kernel, the following vulnerability has been resolved: ovl: keep err zero after successful ovl_cache_get() ovl_iterate_merged() stores PTR_ERR(cache) in err before checking IS_ERR(cache). On success err holds the truncated cache pointer and can be returned as a bogus non-zero error. The syzbot reproducer reaches this through overlay-on-overlay readdir: getdents64 iterate_dir(outer overlay file) ovl_iterate_merged() ovl_cache_get() ovl_dir_read_merged() ovl_dir_read() iterate_dir(inner overlay file) ovl_iterate_merged() Only compute PTR_ERR(cache) on the error path.

The remote Ubuntu 26.04 LTS host has a package installed that is affected by multiple vulnerabilities as referenced in the USN-8489-1 advisory.

    It was discovered that the Linux kernel did not properly handle shared page fragments during socket buffer     operations, collectively known as Dirty Frag. A logic flaw existed in the XFRM ESP-in-TCP subsystem and in     the RxRPC networking subsystem when processing paged fragments. A local attacker could use this to     escalate privileges, or possibly escape a container. (CVE-2026-43284, CVE-2026-43500, CVE-2026-45998,     CVE-2026-46000)

    It was discovered that a logic flaw existed in the XFRM ESP-in-TCP subsystem in the Linux kernel when     handling socket buffer fragments. This flaw is known as Fragnesia. A local attacker could use this to     escalate privileges, or possibly escape a container. (CVE-2026-43503, CVE-2026-46300)

    Qualys discovered that a race condition existed in the ptrace subsystem of the Linux kernel when     privileged processes are exiting. An unprivileged local attacker could use this issue to expose sensitive     information. (CVE-2026-46333)

    Tristan Madani discovered that Ubuntu Linux kernel 6.8, 6.17 and 7.0 contain a memory leak when handling     AppArmor notifications. A local attacker could use this to cause resource exhaustion. (CVE-2026-47326)

    Tristan Madani discovered that Ubuntu Linux kernel 6.8, 6.17 and 7.0 contain a NULL pointer dereference     when handling AppArmor notifications. A local attacker could use this to cause a kernel oops.
    (CVE-2026-47327)

    Tristan Madani discovered that Ubuntu Linux kernel 6.8, 6.17 and 7.0 contained an invalid free when     handling AppArmor notifications. A local attacker could use this to corrupt kernel memory.
    (CVE-2026-47328)

    Tristan Madani discovered that Ubuntu Linux kernel 6.8, 6.17 and 7.0 contained insufficient validation of     AppArmor notification responses. A local attacker could use this to allow crafted responses to be     processed. (CVE-2026-47329)

    Tristan Madani discovered that Ubuntu Linux kernel 6.8, 6.17 and 7.0 used an uninitialized variable when     handling AppArmor notifications. A local attacker could use this to cause incorrect caching of data.
    (CVE-2026-47330)

    Tristan Madani discovered that Ubuntu Linux kernel 6.8, 6.17 and 7.0 contained an out-of-bounds (OOB) read     when handling AppArmor notifications. A local attacker could use this to cause information disclosure of     kernel memory. (CVE-2026-47332)

    Tristan Madani discovered that Ubuntu Linux kernel 6.8, 6.17 and 7.0 contained a out-of-bounds (OOB) read     when handling AppArmor notifications. A local attacker could use this to cause kernel memory corruption     and, theoretically, influence processing of AppArmor policies. (CVE-2026-47333)

    Tristan Madani discovered that Ubuntu Linux kernel 6.8, 6.17 and 7.0 contained incorrect holding of locks     when handling AppArmor notifications. A local attacker could use this to cause a kernel panic or deadlock.
    (CVE-2026-47334)

    Tristan Madani and Trevor Lawrence have each independently discovered that Ubuntu Linux kernel 6.8, 6.17     and 7.0 contained a NULL pointer dereference when handling AppArmor network socket mediation. A local     attacker could use this to cause a kernel oops. (CVE-2026-47337)

    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;

    - x86 architecture;

    - Block layer subsystem;

    - Cryptographic API;

    - Rados block device (RBD) driver;

    - Compressed RAM block device driver;

    - Character device driver;

    - TPM device driver;

    - Hardware crypto device drivers;

    - EDAC drivers;

    - GPU drivers;

    - Greybus drivers;

    - Hardware monitoring drivers;

    - IIO subsystem;

    - InfiniBand drivers;

    - Input Device core drivers;

    - LED subsystem;

    - Multiple devices driver;

    - Media drivers;

    - IBM Advanced System Management driver;

    - MTD block device drivers;

    - Network drivers;

    - Microsoft Azure Network Adapter (MANA) driver;

    - NVME drivers;

    - Device tree and open firmware driver;

    - PCI subsystem;

    - Remote Processor subsystem;

    - SCSI subsystem;

    - SPI subsystem;

    - Thermal drivers;

    - VFIO drivers;

    - Framebuffer layer;

    - 9P distributed file system;

    - AFS file system;

    - Ceph distributed file system;

    - EROFS file system;

    - File systems infrastructure;

    - Ext4 file system;

    - Journaling layer for block devices (JBD2);

    - File system notification infrastructure;

    - NTFS3 file system;

    - OCFS2 file system;

    - Overlay file system;

    - SMB network file system;

    - UDF file system;

    - XFS file system;

    - Codetag library;

    - Memory management;

    - Tracing infrastructure;

    - io_uring subsystem;

    - Locking primitives;

    - Scatterlist API;

    - Heterogeneous memory management;

    - Bluetooth subsystem;

    - Ethernet bridge;

    - CAIF protocol;

    - Ceph Core library;

    - Networking core;

    - IPv4 networking;

    - IPv6 networking;

    - Multipath TCP;

    - Netfilter;

    - Qualcomm IPC Router (QRTR);

    - RDS protocol;

    - RxRPC session sockets;

    - SMC sockets;

    - Stream parser;

    - Landlock security;

    - SELinux security module;

    - ALSA framework;

    - Generic PCM loopback sound driver;

    - Creative Sound Blaster X-Fi driver;

    - USB sound devices; (CVE-2026-43491, CVE-2026-43493, CVE-2026-43494, CVE-2026-43499, CVE-2026-43501,     CVE-2026-45986, CVE-2026-45987, CVE-2026-45988, CVE-2026-45989, CVE-2026-45990, CVE-2026-45991,     CVE-2026-45994, CVE-2026-45995, CVE-2026-45996, CVE-2026-45997, CVE-2026-45999, CVE-2026-46001,     CVE-2026-46002, CVE-2026-46003, CVE-2026-46004, CVE-2026-46005, CVE-2026-46006, CVE-2026-46007,     CVE-2026-46008, CVE-2026-46009, CVE-2026-46010, CVE-2026-46011, CVE-2026-46012, CVE-2026-46013,     CVE-2026-46014, CVE-2026-46015, CVE-2026-46016, CVE-2026-46018, CVE-2026-46019, CVE-2026-46020,     CVE-2026-46021, CVE-2026-46022, CVE-2026-46023, CVE-2026-46024, CVE-2026-46025, CVE-2026-46026,     CVE-2026-46027, CVE-2026-46028, CVE-2026-46029, CVE-2026-46030, CVE-2026-46031, CVE-2026-46032,     CVE-2026-46033, CVE-2026-46034, CVE-2026-46035, CVE-2026-46036, CVE-2026-46037, CVE-2026-46038,     CVE-2026-46039, CVE-2026-46040, CVE-2026-46041, CVE-2026-46042, CVE-2026-46043, CVE-2026-46044,     CVE-2026-46045, CVE-2026-46046, CVE-2026-46047, CVE-2026-46048, CVE-2026-46049, CVE-2026-46050,     CVE-2026-46051, CVE-2026-46052, CVE-2026-46053, CVE-2026-46054, CVE-2026-46056, CVE-2026-46057,     CVE-2026-46058, CVE-2026-46059, CVE-2026-46060, CVE-2026-46061, CVE-2026-46062, CVE-2026-46063,     CVE-2026-46064, CVE-2026-46065, CVE-2026-46066, CVE-2026-46067, CVE-2026-46068, CVE-2026-46069,     CVE-2026-46070, CVE-2026-46071, CVE-2026-46072, CVE-2026-46073, CVE-2026-46074, CVE-2026-46075,     CVE-2026-46076, CVE-2026-46077, CVE-2026-46078, CVE-2026-46079, CVE-2026-46080, CVE-2026-46081,     CVE-2026-46082, CVE-2026-46083, CVE-2026-46084, CVE-2026-46085, CVE-2026-46086, CVE-2026-46087,     CVE-2026-46088, CVE-2026-46089, CVE-2026-46090, CVE-2026-46091, CVE-2026-46092, CVE-2026-46093,     CVE-2026-46094, CVE-2026-46095, CVE-2026-46096, CVE-2026-46097, CVE-2026-46098, CVE-2026-46099,     CVE-2026-46100, CVE-2026-46101, CVE-2026-46102, CVE-2026-46103, CVE-2026-46115, CVE-2026-46119,     CVE-2026-46135, CVE-2026-46137, CVE-2026-46155, CVE-2026-46185, CVE-2026-46195, CVE-2026-46243,     CVE-2026-46244, CVE-2026-46276, CVE-2026-46277, CVE-2026-46278, CVE-2026-46279, CVE-2026-46280,     CVE-2026-46281, CVE-2026-46282, CVE-2026-46283, CVE-2026-46284, CVE-2026-46285, CVE-2026-46286,     CVE-2026-46287, CVE-2026-46288, CVE-2026-46289, CVE-2026-46316, CVE-2026-46323, CVE-2026-46332,     CVE-2026-52904, CVE-2026-52905, CVE-2026-52906, CVE-2026-52907, CVE-2026-52933, CVE-2026-53174)

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.

  - In the Linux kernel, the following vulnerability has been resolved: ovl: keep err zero after successful     ovl_cache_get() ovl_iterate_merged() stores PTR_ERR(cache) in err before checking IS_ERR(cache). On     success err holds the truncated cache pointer and can be returned as a bogus non-zero error. The syzbot     reproducer reaches this through overlay-on-overlay readdir: getdents64 iterate_dir(outer overlay file)     ovl_iterate_merged() ovl_cache_get() ovl_dir_read_merged() ovl_dir_read() iterate_dir(inner overlay file)     ovl_iterate_merged() Only compute PTR_ERR(cache) on the error path. (CVE-2026-53174)

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

ID	Name	Product	Family	Type	Severity
340681	Ubuntu 24.04 LTS / 26.04 LTS / Pro Realtime 24.04 LTS : Linux kernel (NVIDIA) vulnerabilities (USN-8663-1)	Nessus	Ubuntu Local Security Checks	Local	high
340045	Ubuntu 26.04 LTS : Linux kernel (NVIDIA BaseOS) vulnerabilities (USN-8664-1)	Nessus	Ubuntu Local Security Checks	Local	high
325016	Ubuntu 26.04 LTS : Linux kernel (OEM) vulnerabilities (USN-8489-1)	Nessus	Ubuntu Local Security Checks	Local	high
323461	Linux Distros Unpatched Vulnerability : CVE-2026-53174	Nessus	Misc.	Local	high

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CVE-2026-53174

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Tenable Plugins

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