CVE-2023-53147

Medium

In the Linux kernel, the following vulnerability has been resolved: xfrm: add NULL check in xfrm_update_ae_params Normally, x->replay_esn and x->preplay_esn should be allocated at xfrm_alloc_replay_state_esn(...) in xfrm_state_construct(...), hence the xfrm_update_ae_params(...) is okay to update them. However, the current implementation of xfrm_new_ae(...) allows a malicious user to directly dereference a NULL pointer and crash the kernel like below. BUG: kernel NULL pointer dereference, address: 0000000000000000 PGD 8253067 P4D 8253067 PUD 8e0e067 PMD 0 Oops: 0002 [#1] PREEMPT SMP KASAN NOPTI CPU: 0 PID: 98 Comm: poc.npd Not tainted 6.4.0-rc7-00072-gdad9774deaf1 #8 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.0-0-gd239552ce722-prebuilt.qemu.o4 RIP: 0010:memcpy_orig+0xad/0x140 Code: e8 4c 89 5f e0 48 8d 7f e0 73 d2 83 c2 20 48 29 d6 48 29 d7 83 fa 10 72 34 4c 8b 06 4c 8b 4e 08 c RSP: 0018:ffff888008f57658 EFLAGS: 00000202 RAX: 0000000000000000 RBX: ffff888008bd0000 RCX: ffffffff8238e571 RDX: 0000000000000018 RSI: ffff888007f64844 RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: ffff888008f57818 R13: ffff888007f64aa4 R14: 0000000000000000 R15: 0000000000000000 FS: 00000000014013c0(0000) GS:ffff88806d600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000000 CR3: 00000000054d8000 CR4: 00000000000006f0 Call Trace: <TASK> ? __die+0x1f/0x70 ? page_fault_oops+0x1e8/0x500 ? __pfx_is_prefetch.constprop.0+0x10/0x10 ? __pfx_page_fault_oops+0x10/0x10 ? _raw_spin_unlock_irqrestore+0x11/0x40 ? fixup_exception+0x36/0x460 ? _raw_spin_unlock_irqrestore+0x11/0x40 ? exc_page_fault+0x5e/0xc0 ? asm_exc_page_fault+0x26/0x30 ? xfrm_update_ae_params+0xd1/0x260 ? memcpy_orig+0xad/0x140 ? __pfx__raw_spin_lock_bh+0x10/0x10 xfrm_update_ae_params+0xe7/0x260 xfrm_new_ae+0x298/0x4e0 ? __pfx_xfrm_new_ae+0x10/0x10 ? __pfx_xfrm_new_ae+0x10/0x10 xfrm_user_rcv_msg+0x25a/0x410 ? __pfx_xfrm_user_rcv_msg+0x10/0x10 ? __alloc_skb+0xcf/0x210 ? stack_trace_save+0x90/0xd0 ? filter_irq_stacks+0x1c/0x70 ? __stack_depot_save+0x39/0x4e0 ? __kasan_slab_free+0x10a/0x190 ? kmem_cache_free+0x9c/0x340 ? netlink_recvmsg+0x23c/0x660 ? sock_recvmsg+0xeb/0xf0 ? __sys_recvfrom+0x13c/0x1f0 ? __x64_sys_recvfrom+0x71/0x90 ? do_syscall_64+0x3f/0x90 ? entry_SYSCALL_64_after_hwframe+0x72/0xdc ? copyout+0x3e/0x50 netlink_rcv_skb+0xd6/0x210 ? __pfx_xfrm_user_rcv_msg+0x10/0x10 ? __pfx_netlink_rcv_skb+0x10/0x10 ? __pfx_sock_has_perm+0x10/0x10 ? mutex_lock+0x8d/0xe0 ? __pfx_mutex_lock+0x10/0x10 xfrm_netlink_rcv+0x44/0x50 netlink_unicast+0x36f/0x4c0 ? __pfx_netlink_unicast+0x10/0x10 ? netlink_recvmsg+0x500/0x660 netlink_sendmsg+0x3b7/0x700 This Null-ptr-deref bug is assigned CVE-2023-3772. And this commit adds additional NULL check in xfrm_update_ae_params to fix the NPD.

Package Linux Kernel
Published 2025-09-15
Last modified 2025-11-25
CVSS version 3.1
Patch available
Yes

CVSS 3.1 score

5.5

out of 10
Medium
Attack Vector
Local
Attack Complexity
Low
Privileges Required
Low
User Interaction
None
Scope
Unchanged
Confidentiality
Low
Integrity
None
Availability
High
Vector string
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Weakness type

CWE-476

CVE-2023-53147 is a NULL Pointer Dereference vulnerability

What is NULL Pointer Dereference?

The product dereferences a pointer that it expects to be valid but is NULL, typically causing a crash. Learn more on MITRE CWE

Affected versions

Linux kernel versions 2.6.39 and later are affected. Fixed in 4.14.324, 4.19.293, 5.4.255, 5.10.192, 5.15.128, 6.1.47, 6.4.12, 6.5 and their respective stable series.

Affected from
≥ 2.6.39
Fixed in
✓ 4.14.324 4.14.x ✓ 4.19.293 4.19.x ✓ 5.4.255 5.4.x ✓ 5.10.192 5.10.x ✓ 5.15.128 5.15.x ✓ 6.1.47 6.1.x ✓ 6.4.12 6.4.x ✓ 6.5

References

The following references provide additional information about CVE-2023-53147 including vendor advisories, patch commits, exploit details, and third-party analysis. Links are sourced from the NIST NVD database.

Frequently asked questions

  • What is CVE-2023-53147?

    CVE-2023-53147 is a Medium severity Linux kernel vulnerability with a CVSS score of 5.5 out of 10 , classified as a NULL Pointer Dereference flaw (CWE-476) . It affects Linux kernel versions from 2.6.39 onward and has been patched in 4.14.324, 4.19.293, 5.4.255 and others. CVE-2023-53147 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

  • What is the CVSS score for CVE-2023-53147?

    CVE-2023-53147 has a CVSS score of 5.5 out of 10, rated Medium severity (CVSS 3.1). The vector string is CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H .

  • Is there a patch available for CVE-2023-53147?

    Yes — CVE-2023-53147 has been patched. Fixed versions include 4.14.324, 4.19.293, 5.4.255 and others. If you are running Linux kernel 2.6.39 or later up to the fix versions, apply the relevant patch for your kernel branch.

  • Is CVE-2023-53147 actively exploited?

    No — CVE-2023-53147 has not been confirmed as actively exploited. It is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.

  • What is NULL Pointer Dereference (CWE-476)?

    The product dereferences a pointer that it expects to be valid but is NULL, typically causing a crash. View CWE-476 on MITRE CWE →