Linux Kernel up to 6.5.3 net net/core/sock.c sk_mc_loop denial of service

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4.6$0-$5k0.00

Summaryinfo

A vulnerability was found in Linux Kernel up to 6.5.3. It has been declared as critical. Affected by this issue is the function sk_mc_loop of the file net/core/sock.c of the component net. Executing a manipulation can lead to denial of service. The identification of this vulnerability is CVE-2023-53831. There is no exploit available. It is recommended to upgrade the affected component.

Detailsinfo

A vulnerability has been found in Linux Kernel up to 6.5.3 and classified as critical. This vulnerability affects the function sk_mc_loop of the file net/core/sock.c of the component net. The manipulation with an unknown input leads to a denial of service vulnerability. The CWE definition for the vulnerability is CWE-404. The product does not release or incorrectly releases a resource before it is made available for re-use. As an impact it is known to affect availability. CVE summarizes:

In the Linux kernel, the following vulnerability has been resolved: net: read sk->sk_family once in sk_mc_loop() syzbot is playing with IPV6_ADDRFORM quite a lot these days, and managed to hit the WARN_ON_ONCE(1) in sk_mc_loop() We have many more similar issues to fix. WARNING: CPU: 1 PID: 1593 at net/core/sock.c:782 sk_mc_loop+0x165/0x260 Modules linked in: CPU: 1 PID: 1593 Comm: kworker/1:3 Not tainted 6.1.40-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/26/2023 Workqueue: events_power_efficient gc_worker RIP: 0010:sk_mc_loop+0x165/0x260 net/core/sock.c:782 Code: 34 1b fd 49 81 c7 18 05 00 00 4c 89 f8 48 c1 e8 03 42 80 3c 20 00 74 08 4c 89 ff e8 25 36 6d fd 4d 8b 37 eb 13 e8 db 33 1b fd <0f> 0b b3 01 eb 34 e8 d0 33 1b fd 45 31 f6 49 83 c6 38 4c 89 f0 48 RSP: 0018:ffffc90000388530 EFLAGS: 00010246 RAX: ffffffff846d9b55 RBX: 0000000000000011 RCX: ffff88814f884980 RDX: 0000000000000102 RSI: ffffffff87ae5160 RDI: 0000000000000011 RBP: ffffc90000388550 R08: 0000000000000003 R09: ffffffff846d9a65 R10: 0000000000000002 R11: ffff88814f884980 R12: dffffc0000000000 R13: ffff88810dbee000 R14: 0000000000000010 R15: ffff888150084000 FS: 0000000000000000(0000) GS:ffff8881f6b00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000020000180 CR3: 000000014ee5b000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <IRQ> [<ffffffff8507734f>] ip6_finish_output2+0x33f/0x1ae0 net/ipv6/ip6_output.c:83 [<ffffffff85062766>] __ip6_finish_output net/ipv6/ip6_output.c:200 [inline] [<ffffffff85062766>] ip6_finish_output+0x6c6/0xb10 net/ipv6/ip6_output.c:211 [<ffffffff85061f8c>] NF_HOOK_COND include/linux/netfilter.h:298 [inline] [<ffffffff85061f8c>] ip6_output+0x2bc/0x3d0 net/ipv6/ip6_output.c:232 [<ffffffff852071cf>] dst_output include/net/dst.h:444 [inline] [<ffffffff852071cf>] ip6_local_out+0x10f/0x140 net/ipv6/output_core.c:161 [<ffffffff83618fb4>] ipvlan_process_v6_outbound drivers/net/ipvlan/ipvlan_core.c:483 [inline] [<ffffffff83618fb4>] ipvlan_process_outbound drivers/net/ipvlan/ipvlan_core.c:529 [inline] [<ffffffff83618fb4>] ipvlan_xmit_mode_l3 drivers/net/ipvlan/ipvlan_core.c:602 [inline] [<ffffffff83618fb4>] ipvlan_queue_xmit+0x1174/0x1be0 drivers/net/ipvlan/ipvlan_core.c:677 [<ffffffff8361ddd9>] ipvlan_start_xmit+0x49/0x100 drivers/net/ipvlan/ipvlan_main.c:229 [<ffffffff84763fc0>] netdev_start_xmit include/linux/netdevice.h:4925 [inline] [<ffffffff84763fc0>] xmit_one net/core/dev.c:3644 [inline] [<ffffffff84763fc0>] dev_hard_start_xmit+0x320/0x980 net/core/dev.c:3660 [<ffffffff8494c650>] sch_direct_xmit+0x2a0/0x9c0 net/sched/sch_generic.c:342 [<ffffffff8494d883>] qdisc_restart net/sched/sch_generic.c:407 [inline] [<ffffffff8494d883>] __qdisc_run+0xb13/0x1e70 net/sched/sch_generic.c:415 [<ffffffff8478c426>] qdisc_run+0xd6/0x260 include/net/pkt_sched.h:125 [<ffffffff84796eac>] net_tx_action+0x7ac/0x940 net/core/dev.c:5247 [<ffffffff858002bd>] __do_softirq+0x2bd/0x9bd kernel/softirq.c:599 [<ffffffff814c3fe8>] invoke_softirq kernel/softirq.c:430 [inline] [<ffffffff814c3fe8>] __irq_exit_rcu+0xc8/0x170 kernel/softirq.c:683 [<ffffffff814c3f09>] irq_exit_rcu+0x9/0x20 kernel/softirq.c:695

The advisory is shared for download at git.kernel.org. This vulnerability was named CVE-2023-53831 since 12/09/2025. The exploitation appears to be difficult. There are known technical details, but no exploit is available.

The vulnerability scanner Nessus provides a plugin with the ID 302405 (EulerOS 2.0 SP10 : kernel (EulerOS-SA-2026-1313)), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 4.14.326, 4.19.295, 5.4.257, 5.10.195, 5.15.132, 6.1.54 or 6.5.4 eliminates this vulnerability. Applying the patch 7586a66b9c4f1b8a825ea1dfa3a91aad5cc7b89b/e918d0211ffbaf039447334c3460cafee1ce0157/41f10a4d78fe69d685a3172e6884297f233dcf95/895dc4c47171a20035cdaa8d74c1c1e97f2fc974/ed4e0adfa407ab65dd73b8862ebf2f308a0349d2/9036b6342fcdab190d6edce3dd447859c1de90fc/b1f5b890b89cb38a6c0bac91984d56cd69808e8c/a3e0fdf71bbe031de845e8e08ed7fba49f9c702c is able to eliminate this problem. The bugfix is ready for download at git.kernel.org. The best possible mitigation is suggested to be upgrading to the latest version.

The vulnerability is also documented in the databases at Tenable (302405) and CERT Bund (WID-SEC-2025-2765). Once again VulDB remains the best source for vulnerability data.

Affected

  • Debian Linux
  • Amazon Linux 2
  • Red Hat Enterprise Linux
  • Ubuntu Linux
  • SUSE Linux
  • Oracle Linux
  • SUSE openSUSE
  • Open Source Linux Kernel
  • RESF Rocky Linux

Productinfo

Type

Vendor

Name

Version

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 4.8
VulDB Meta Temp Score: 4.6

VulDB Base Score: 4.8
VulDB Temp Score: 4.6
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

AVACAuCIA
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💳💳💳💳💳💳
💳💳💳💳💳💳
VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Denial of service
CWE: CWE-404
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Partially

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Nessus ID: 302405
Nessus Name: EulerOS 2.0 SP10 : kernel (EulerOS-SA-2026-1313)

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Kernel 4.14.326/4.19.295/5.4.257/5.10.195/5.15.132/6.1.54/6.5.4
Patch: 7586a66b9c4f1b8a825ea1dfa3a91aad5cc7b89b/e918d0211ffbaf039447334c3460cafee1ce0157/41f10a4d78fe69d685a3172e6884297f233dcf95/895dc4c47171a20035cdaa8d74c1c1e97f2fc974/ed4e0adfa407ab65dd73b8862ebf2f308a0349d2/9036b6342fcdab190d6edce3dd447859c1de90fc/b1f5b890b89cb38a6c0bac91984d56cd69808e8c/a3e0fdf71bbe031de845e8e08ed7fba49f9c702c

Timelineinfo

12/09/2025 Advisory disclosed
12/09/2025 +0 days CVE reserved
12/09/2025 +0 days VulDB entry created
03/30/2026 +110 days VulDB entry last update

Sourcesinfo

Vendor: kernel.org

Advisory: git.kernel.org
Status: Confirmed

CVE: CVE-2023-53831 (🔒)
GCVE (CVE): GCVE-0-2023-53831
GCVE (VulDB): GCVE-100-334984
CERT Bund: WID-SEC-2025-2765 - Linux Kernel: Mehrere Schwachstellen erm&ouml;glichen Denial of Service

Entryinfo

Created: 12/09/2025 09:14
Updated: 03/30/2026 01:53
Changes: 12/09/2025 09:14 (60), 12/10/2025 01:38 (1), 03/16/2026 21:23 (2), 03/30/2026 01:53 (7)
Complete: 🔍
Cache ID: 216:134:103

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