In the Linux kernel, the following vulnerability has been resolved: af_unix: fix struct pid leaks in OOB support syzbot reported struct pid leak [1]. Issue is that queue_oob() calls maybe_add_creds() which potentially holds a reference on a pid. But skb->destructor is not set (either directly or by calling unix_scm_to_skb()) This means that subsequent kfree_skb() or consume_skb() would leak this reference. In this fix, I chose to fully support scm even for the OOB message. [1] BUG: memory leak unreferenced object 0xffff8881053e7f80 (size 128): comm "syz-executor242", pid 5066, jiffies 4294946079 (age 13.220s) hex dump (first 32 bytes): 01 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ backtrace: [<ffffffff812ae26a>] alloc_pid+0x6a/0x560 kernel/pid.c:180 [<ffffffff812718df>] copy_process+0x169f/0x26c0 kernel/fork.c:2285 [<ffffffff81272b37>] kernel_clone+0xf7/0x610 kernel/fork.c:2684 [<ffffffff812730cc>] __do_sys_clone+0x7c/0xb0 kernel/fork.c:2825 [<ffffffff849ad699>] do_syscall_x64 arch/x86/entry/common.c:50 [inline] [<ffffffff849ad699>] do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80 [<ffffffff84a0008b>] entry_SYSCALL_64_after_hwframe+0x63/0xcd

The version of kernel installed on the remote host is prior to 5.15.104-63.140. It is, therefore, affected by multiple vulnerabilities as referenced in the ALAS2KERNEL-5.15-2023-019 advisory.

    2025-07-03: CVE-2023-53131 was added to this advisory.

    2025-06-27: CVE-2023-53123 was added to this advisory.

    2025-06-27: CVE-2023-53137 was added to this advisory.

    2025-06-19: CVE-2023-53075 was added to this advisory.

    2025-06-19: CVE-2023-53109 was added to this advisory.

    2025-06-19: CVE-2023-53101 was added to this advisory.

    2025-06-19: CVE-2023-53140 was added to this advisory.

    2025-06-19: CVE-2023-53136 was added to this advisory.

    2025-06-19: CVE-2023-53089 was added to this advisory.

    2025-06-19: CVE-2023-53100 was added to this advisory.

    2025-06-19: CVE-2023-53091 was added to this advisory.

    2025-06-19: CVE-2023-53133 was added to this advisory.

    2024-06-06: CVE-2023-30456 was added to this advisory.

    A use-after-free vulnerability in the Linux Kernel Performance Events system can be exploited to achieve     local privilege escalation.

    The perf_group_detach function did not check the event's siblings' attach_state before calling     add_event_to_groups(), but remove_on_exec made it possible to call list_del_event() on before detaching     from their group, making it possible to use a dangling pointer causing a use-after-free vulnerability.

    We recommend upgrading past commit fd0815f632c24878e325821943edccc7fde947a2. (CVE-2023-2235)

    An issue was discovered in arch/x86/kvm/vmx/nested.c in the Linux kernel before 6.2.8. nVMX on x86_64     lacks consistency checks for CR0 and CR4. (CVE-2023-30456)

    In the Linux kernel, the following vulnerability has been resolved:

    ftrace: Fix invalid address access in lookup_rec() when index is 0 (CVE-2023-53075)

    In the Linux kernel, the following vulnerability has been resolved:

    ext4: fix task hung in ext4_xattr_delete_inode (CVE-2023-53089)

    In the Linux kernel, the following vulnerability has been resolved:

    ext4: update s_journal_inum if it changes after journal replay (CVE-2023-53091)

    In the Linux kernel, the following vulnerability has been resolved:

    ext4: fix WARNING in ext4_update_inline_data (CVE-2023-53100)

    In the Linux kernel, the following vulnerability has been resolved:

    ext4: zero i_disksize when initializing the bootloader inode (CVE-2023-53101)

    In the Linux kernel, the following vulnerability has been resolved:

    net: tunnels: annotate lockless accesses to dev->needed_headroom (CVE-2023-53109)

    In the Linux kernel, the following vulnerability has been resolved:

    PCI: s390: Fix use-after-free of PCI resources with per-function hotplug (CVE-2023-53123)

    In the Linux kernel, the following vulnerability has been resolved:

    SUNRPC: Fix a server shutdown leak (CVE-2023-53131)

    In the Linux kernel, the following vulnerability has been resolved:

    bpf, sockmap: Fix an infinite loop error when len is 0 in tcp_bpf_recvmsg_parser() (CVE-2023-53133)

    In the Linux kernel, the following vulnerability has been resolved:

    af_unix: fix struct pid leaks in OOB support (CVE-2023-53136)

    In the Linux kernel, the following vulnerability has been resolved:

    ext4: Fix possible corruption when moving a directory (CVE-2023-53137)

    In the Linux kernel, the following vulnerability has been resolved:

    scsi: core: Remove the /proc/scsi/${proc_name} directory earlier (CVE-2023-53140)

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

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

It is, therefore, affected by multiple vulnerabilities as referenced in the ALAS2023-2023-148 advisory.

    In the Linux kernel, the following vulnerability has been resolved:

    KVM: VMX: Do _all_ initialization before exposing /dev/kvm to userspace (CVE-2022-49932)

    A use-after-free vulnerability in the Linux Kernel Performance Events system can be exploited to achieve     local privilege escalation.

    The perf_group_detach function did not check the event's siblings' attach_state before calling     add_event_to_groups(), but remove_on_exec made it possible to call list_del_event() on before detaching     from their group, making it possible to use a dangling pointer causing a use-after-free vulnerability.

    We recommend upgrading past commit fd0815f632c24878e325821943edccc7fde947a2. (CVE-2023-2235)

    do_tls_getsockopt in net/tls/tls_main.c in the Linux kernel through 6.2.6 lacks a lock_sock call, leading     to a race condition (with a resultant use-after-free or NULL pointer dereference). (CVE-2023-28466)

    An issue was discovered in arch/x86/kvm/vmx/nested.c in the Linux kernel before 6.2.8. nVMX on x86_64     lacks consistency checks for CR0 and CR4. (CVE-2023-30456)

    In the Linux kernel, the following vulnerability has been resolved:

    ftrace: Fix invalid address access in lookup_rec() when index is 0 (CVE-2023-53075)

    In the Linux kernel, the following vulnerability has been resolved:

    ext4: fix task hung in ext4_xattr_delete_inode (CVE-2023-53089)

    In the Linux kernel, the following vulnerability has been resolved:

    ext4: update s_journal_inum if it changes after journal replay (CVE-2023-53091)

    In the Linux kernel, the following vulnerability has been resolved:

    drm/ttm: Fix a NULL pointer dereference (CVE-2023-53095)

    In the Linux kernel, the following vulnerability has been resolved:

    ext4: fix WARNING in ext4_update_inline_data (CVE-2023-53100)

    In the Linux kernel, the following vulnerability has been resolved:

    ext4: zero i_disksize when initializing the bootloader inode (CVE-2023-53101)

    In the Linux kernel, the following vulnerability has been resolved:

    veth: Fix use after free in XDP_REDIRECT (CVE-2023-53107)

    In the Linux kernel, the following vulnerability has been resolved:

    net: tunnels: annotate lockless accesses to dev->needed_headroom (CVE-2023-53109)

    In the Linux kernel, the following vulnerability has been resolved:

    PCI: s390: Fix use-after-free of PCI resources with per-function hotplug (CVE-2023-53123)

    In the Linux kernel, the following vulnerability has been resolved:

    SUNRPC: Fix a server shutdown leak (CVE-2023-53131)

    In the Linux kernel, the following vulnerability has been resolved:

    bpf, sockmap: Fix an infinite loop error when len is 0 in tcp_bpf_recvmsg_parser() (CVE-2023-53133)

    In the Linux kernel, the following vulnerability has been resolved:

    af_unix: fix struct pid leaks in OOB support (CVE-2023-53136)

    In the Linux kernel, the following vulnerability has been resolved:

    ext4: Fix possible corruption when moving a directory (CVE-2023-53137)

    In the Linux kernel, the following vulnerability has been resolved:

    scsi: core: Remove the /proc/scsi/${proc_name} directory earlier (CVE-2023-53140)

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

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

ID	Name	Product	Family	Severity
176754	Amazon Linux 2 : kernel (ALASKERNEL-5.15-2023-019)	Nessus	Amazon Linux Local Security Checks	high
173854	Amazon Linux 2023 : bpftool, kernel, kernel-devel (ALAS2023-2023-148)	Nessus	Amazon Linux Local Security Checks	high

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