CVE-2023-53439

Medium

In the Linux kernel, the following vulnerability has been resolved: net: skb_partial_csum_set() fix against transport header magic value skb->transport_header uses the special 0xFFFF value to mark if the transport header was set or not. We must prevent callers to accidentaly set skb->transport_header to 0xFFFF. Note that only fuzzers can possibly do this today. syzbot reported: WARNING: CPU: 0 PID: 2340 at include/linux/skbuff.h:2847 skb_transport_offset include/linux/skbuff.h:2956 [inline] WARNING: CPU: 0 PID: 2340 at include/linux/skbuff.h:2847 virtio_net_hdr_to_skb+0xbcc/0x10c0 include/linux/virtio_net.h:103 Modules linked in: CPU: 0 PID: 2340 Comm: syz-executor.0 Not tainted 6.3.0-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/14/2023 RIP: 0010:skb_transport_header include/linux/skbuff.h:2847 [inline] RIP: 0010:skb_transport_offset include/linux/skbuff.h:2956 [inline] RIP: 0010:virtio_net_hdr_to_skb+0xbcc/0x10c0 include/linux/virtio_net.h:103 Code: 41 39 df 0f 82 c3 04 00 00 48 8b 7c 24 10 44 89 e6 e8 08 6e 59 ff 48 85 c0 74 54 e8 ce 36 7e fc e9 37 f8 ff ff e8 c4 36 7e fc <0f> 0b e9 93 f8 ff ff 44 89 f7 44 89 e6 e8 32 38 7e fc 45 39 e6 0f RSP: 0018:ffffc90004497880 EFLAGS: 00010293 RAX: ffffffff84fea55c RBX: 000000000000ffff RCX: ffff888120be2100 RDX: 0000000000000000 RSI: 000000000000ffff RDI: 000000000000ffff RBP: ffffc90004497990 R08: ffffffff84fe9de5 R09: 0000000000000034 R10: ffffea00048ebd80 R11: 0000000000000034 R12: ffff88811dc2d9c8 R13: dffffc0000000000 R14: ffff88811dc2d9ae R15: 1ffff11023b85b35 FS: 00007f9211a59700(0000) GS:ffff8881f6c00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00000000200002c0 CR3: 00000001215a5000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> packet_snd net/packet/af_packet.c:3076 [inline] packet_sendmsg+0x4590/0x61a0 net/packet/af_packet.c:3115 sock_sendmsg_nosec net/socket.c:724 [inline] sock_sendmsg net/socket.c:747 [inline] __sys_sendto+0x472/0x630 net/socket.c:2144 __do_sys_sendto net/socket.c:2156 [inline] __se_sys_sendto net/socket.c:2152 [inline] __x64_sys_sendto+0xe5/0x100 net/socket.c:2152 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x2f/0x50 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7f9210c8c169 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 f1 19 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f9211a59168 EFLAGS: 00000246 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 00007f9210dabf80 RCX: 00007f9210c8c169 RDX: 000000000000ffed RSI: 00000000200000c0 RDI: 0000000000000003 RBP: 00007f9210ce7ca1 R08: 0000000020000540 R09: 0000000000000014 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffe135d65cf R14: 00007f9211a59300 R15: 0000000000022000

Package Linux Kernel
Published 2025-09-18
Last modified 2026-01-14
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-401

CVE-2023-53439 is a Memory Leak vulnerability

What is Memory Leak?

The product does not release memory after use, causing gradual resource exhaustion. Learn more on MITRE CWE

Affected versions

Linux kernel versions 5.19 and later are affected. Fixed in 6.1.30, 6.3.4, 6.4 and their respective stable series.

Affected from
≥ 5.19
Fixed in
✓ 6.1.30 6.1.x ✓ 6.3.4 6.3.x ✓ 6.4

References

The following references provide additional information about CVE-2023-53439 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-2023-53439?

    CVE-2023-53439 is a Medium severity Linux kernel vulnerability with a CVSS score of 5.5 out of 10 , classified as a Memory Leak flaw (CWE-401) . It affects Linux kernel versions from 5.19 onward and has been patched in 6.1.30, 6.3.4 and 6.4. CVE-2023-53439 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

  • What is the CVSS score for CVE-2023-53439?

    CVE-2023-53439 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-2023-53439?

    Yes — CVE-2023-53439 has been patched. Fixed versions include 6.1.30, 6.3.4 and 6.4. If you are running Linux kernel 5.19 or later up to the fix versions, apply the relevant patch for your kernel branch.

  • Is CVE-2023-53439 actively exploited?

    No — CVE-2023-53439 has not been confirmed as actively exploited. It is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.

  • What is Memory Leak (CWE-401)?

    The product does not release memory after use, causing gradual resource exhaustion. View CWE-401 on MITRE CWE →