In the Linux kernel, the following vulnerability has been resolved: af_unix: Don't leave consecutive consumed OOB skbs. Jann Horn reported a use-after-free in unix_stream_read_generic(). The following sequences reproduce the issue: $ python3 from socket import * s1, s2 = socketpair(AF_UNIX, SOCK_STREAM) s1.send(b'x', MSG_OOB) s2.recv(1, MSG_OOB) # leave a consumed OOB skb s1.send(b'y', MSG_OOB) s2.recv(1, MSG_OOB) # leave a consumed OOB skb s1.send(b'z', MSG_OOB) s2.recv(1) # recv 'z' illegally s2.recv(1, MSG_OOB) # access 'z' skb (use-after-free) Even though a user reads OOB data, the skb holding the data stays on the recv queue to mark the OOB boundary and break the next recv(). After the last send() in the scenario above, the sk2's recv queue has 2 leading consumed OOB skbs and 1 real OOB skb. Then, the following happens during the next recv() without MSG_OOB 1. unix_stream_read_generic() peeks the first consumed OOB skb 2. manage_oob() returns the next consumed OOB skb 3. unix_stream_read_generic() fetches the next not-yet-consumed OOB skb 4. unix_stream_read_generic() reads and frees the OOB skb , and the last recv(MSG_OOB) triggers KASAN splat. The 3. above occurs because of the SO_PEEK_OFF code, which does not expect unix_skb_len(skb) to be 0, but this is true for such consumed OOB skbs. while (skip >= unix_skb_len(skb)) { skip -= unix_skb_len(skb); skb = skb_peek_next(skb, &sk->sk_receive_queue); ... } In addition to this use-after-free, there is another issue that ioctl(SIOCATMARK) does not function properly with consecutive consumed OOB skbs. So, nothing good comes out of such a situation. Instead of complicating manage_oob(), ioctl() handling, and the next ECONNRESET fix by introducing a loop for consecutive consumed OOB skbs, let's not leave such consecutive OOB unnecessarily. Now, while receiving an OOB skb in unix_stream_recv_urg(), if its previous skb is a consumed OOB skb, it is freed. [0]: BUG: KASAN: slab-use-after-free in unix_stream_read_actor (net/unix/af_unix.c:3027) Read of size 4 at addr ffff888106ef2904 by task python3/315 CPU: 2 UID: 0 PID: 315 Comm: python3 Not tainted 6.16.0-rc1-00407-gec315832f6f9 #8 PREEMPT(voluntary) Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.3-4.fc42 04/01/2014 Call Trace: <TASK> dump_stack_lvl (lib/dump_stack.c:122) print_report (mm/kasan/report.c:409 mm/kasan/report.c:521) kasan_report (mm/kasan/report.c:636) unix_stream_read_actor (net/unix/af_unix.c:3027) unix_stream_read_generic (net/unix/af_unix.c:2708 net/unix/af_unix.c:2847) unix_stream_recvmsg (net/unix/af_unix.c:3048) sock_recvmsg (net/socket.c:1063 (discriminator 20) net/socket.c:1085 (discriminator 20)) __sys_recvfrom (net/socket.c:2278) __x64_sys_recvfrom (net/socket.c:2291 (discriminator 1) net/socket.c:2287 (discriminator 1) net/socket.c:2287 (discriminator 1)) do_syscall_64 (arch/x86/entry/syscall_64.c:63 (discriminator 1) arch/x86/entry/syscall_64.c:94 (discriminator 1)) entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:130) RIP: 0033:0x7f8911fcea06 Code: 5d e8 41 8b 93 08 03 00 00 59 5e 48 83 f8 fc 75 19 83 e2 39 83 fa 08 75 11 e8 26 ff ff ff 66 0f 1f 44 00 00 48 8b 45 10 0f 05 <48> 8b 5d f8 c9 c3 0f 1f 40 00 f3 0f 1e fa 55 48 89 e5 48 83 ec 08 RSP: 002b:00007fffdb0dccb0 EFLAGS: 00000202 ORIG_RAX: 000000000000002d RAX: ffffffffffffffda RBX: 00007fffdb0dcdc8 RCX: 00007f8911fcea06 RDX: 0000000000000001 RSI: 00007f8911a5e060 RDI: 0000000000000006 RBP: 00007fffdb0dccd0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000202 R12: 00007f89119a7d20 R13: ffffffffc4653600 R14: 0000000000000000 R15: 0000000000000000 </TASK> Allocated by task 315: kasan_save_stack (mm/kasan/common.c:48) kasan_save_track (mm/kasan/common.c:60 (discriminator 1) mm/kasan/common.c:69 (discriminator 1)) __kasan_slab_alloc (mm/kasan/common.c:348) kmem_cache_alloc_ ---truncated---

vendor_unpatched cve-2025-38236: Unpatched CVEs for Debian Linux, Ubuntu Linux (cve-2025-38236)

It is, therefore, affected by multiple vulnerabilities as referenced in the ALAS2023-2025-1111 advisory.

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

    Drivers: hv: vmbus: Leak pages if set_memory_encrypted() fails (CVE-2024-36913)

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

    xfs: don't walk off the end of a directory data block (CVE-2024-41013)

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

    mm: hugetlb: independent PMD page table shared count (CVE-2024-57883)

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

    bpf: Fix kmemleak warning for percpu hashmap (CVE-2025-37807)

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

    mm/huge_memory: fix dereferencing invalid pmd migration entry (CVE-2025-37958)

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

    net_sched: prio: fix a race in prio_tune() (CVE-2025-38083)

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

    mm/hugetlb: unshare page tables during VMA split, not before (CVE-2025-38084)

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

    net_sched: red: fix a race in __red_change() (CVE-2025-38108)

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

    net/mdiobus: Fix potential out-of-bounds read/write access (CVE-2025-38111)

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

    net: Fix TOCTOU issue in sk_is_readable() (CVE-2025-38112)

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

    ACPI: CPPC: Fix NULL pointer dereference when nosmp is used (CVE-2025-38113)

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

    net_sched: sch_sfq: fix a potential crash on gso_skb handling (CVE-2025-38115)

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

    net: fix udp gso skb_segment after pull from frag_list (CVE-2025-38124)

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

    net: openvswitch: Fix the dead loop of MPLS parse (CVE-2025-38146)

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

    calipso: Don't call calipso functions for AF_INET sk. (CVE-2025-38147)

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

    bpf, sockmap: Avoid using sk_socket after free when sending (CVE-2025-38154)

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

    RDMA/mlx5: Fix error flow upon firmware failure for RQ destruction (CVE-2025-38161)

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

    net_sched: sch_sfq: reject invalid perturb period (CVE-2025-38193)

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

    fbdev: Fix do_register_framebuffer to prevent null-ptr-deref in fb_videomode_to_var (CVE-2025-38215)

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

    nfsd: Initialize ssc before laundromat_work to prevent NULL dereference (CVE-2025-38231)

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

    af_unix: Don't leave consecutive consumed OOB skbs. (CVE-2025-38236)

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

    bpf: Avoid __bpf_prog_ret0_warn when jit fails (CVE-2025-38280)

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

    bpf: Fix WARN() in get_bpf_raw_tp_regs (CVE-2025-38285)

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

    ptp: remove ptp->n_vclocks check logic in ptp_vclock_in_use() (CVE-2025-38305)

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

    fbdev: core: fbcvt: avoid division by 0 in fb_cvt_hperiod() (CVE-2025-38312)

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

    mpls: Use rcu_dereference_rtnl() in mpls_route_input_rcu(). (CVE-2025-38324)

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.

An update of the linux package has been released.

ID	Name	Product	Family	Severity
243500	Amazon Linux 2023 : bpftool, kernel, kernel-devel (ALAS2023-2025-1111)	Nessus	Amazon Linux Local Security Checks	high
242163	Photon OS 5.0: Linux PHSA-2025-5.0-0558	Nessus	PhotonOS Local Security Checks	high

Detections

Analytics

CVE-2025-38236

high

Tenable Plugins

Coming Soon

high

high