CVE-2023-53365: ip6mr: Fix skb_under_panic in ip6mr_cache_report()

Published Sep 17, 2025
·
Updated

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

ip6mr: Fix skbunderpanic in ip6mrcachereport()

skbuff: skbunderpanic: text:ffffffff88771f69 len:56 put:-4 head:ffff88805f86a800 data:ffff887f5f86a850 tail:0x88 end:0x2c0 dev:pim6reg ------------[ cut here ]------------ kernel BUG at net/core/skbuff.c:192! invalid opcode: 0000 [#1] PREEMPT SMP KASAN CPU: 2 PID: 22968 Comm: kworker/2:11 Not tainted 6.5.0-rc3-00044-g0a8db05b571a #236 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.15.0-1 04/01/2014 Workqueue: ipv6addrconf addrconfdadwork RIP: 0010:skbpanic+0x152/0x1d0 Call Trace: <TASK> skbpush+0xc4/0xe0 ip6mrcachereport+0xd69/0x19b0 regvifxmit+0x406/0x690 devhardstartxmit+0x17e/0x6e0 devqueuexmit+0x2d6a/0x3d20 vlandevhardstartxmit+0x3ab/0x5c0 devhardstartxmit+0x17e/0x6e0 devqueuexmit+0x2d6a/0x3d20 neighconnectedoutput+0x3ed/0x570 ip6finishoutput2+0x5b5/0x1950 ip6finishoutput+0x693/0x11c0 ip6output+0x24b/0x880 NFHOOK.constprop.0+0xfd/0x530 ndiscsendskb+0x9db/0x1400 ndiscsendrs+0x12a/0x6c0 addrconfdadcompleted+0x3c9/0xea0 addrconfdadwork+0x849/0x1420 processonework+0xa22/0x16e0 workerthread+0x679/0x10c0 retfromfork+0x28/0x60 retfromforkasm+0x11/0x20

When setup a vlan device on dev pim6reg, DAD ns packet may sent on regvifxmit(). regvifxmit() ip6mrcachereport() skbpush(skb, -skbnetworkoffset(pkt));//skbnetworkoffset(pkt) is 4 And skbpush declared as: void skbpush(struct skbuff skb, unsigned int len); skb->data -= len; //0xffff88805f86a84c - 0xfffffffc = 0xffff887f5f86a850 skb->data is set to 0xffff887f5f86a850, which is invalid mem addr, lead to skbpush() fails.

Affected Software

12 affected components
Linux Linux kernel
Linux Linux kernel>=2.6.26<4.14.322
Linux Linux kernel>=4.15<4.19.291
Linux Linux kernel>=4.20<5.4.253
Linux Linux kernel>=5.5<5.10.190
Linux Linux kernel>=5.11<5.15.126
Linux Linux kernel>=5.16<6.1.45
Linux Linux kernel>=6.2<6.4.10
Linux Linux kernel=6.5-rc1
Linux Linux kernel=6.5-rc2
Linux Linux kernel=6.5-rc3
Linux Linux kernel=6.5-rc4

Event History

Sep 17, 2025
CVE Published
via MITRE·02:56 PM
Data Sourced
via MITRE·02:56 PM
Description
Data Sourced
via Red Hat·03:03 PM
DescriptionSeverityAffected Software
Data Sourced
via NVD·03:15 PM
RemedyDescriptionSeverityAffected Software

Frequently Asked Questions

1

What is the severity of CVE-2023-53365?

CVE-2023-53365 has been labeled with a high severity level due to its potential to cause skb_under_panic in the Linux kernel.

2

How do I fix CVE-2023-53365?

To resolve CVE-2023-53365, update your Linux kernel to the latest stable version that includes the fix.

3

What does CVE-2023-53365 affect?

CVE-2023-53365 specifically affects the Linux kernel and its handling of ip6mr_cache_report.

4

What is the impact of CVE-2023-53365?

The impact of CVE-2023-53365 can lead to system crashes due to memory management issues within the kernel.

5

When was CVE-2023-53365 first reported?

CVE-2023-53365 was reported in late 2023, following the discovery of the skb_under_panic vulnerability in the Linux kernel.

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