CVE-2023-53365 [Medium] | Security Vulnerability in Linux Kernel

In the Linux kernel, the following vulnerability has been resolved: ip6mr: Fix skb_under_panic in ip6mr_cache_report() skbuff: skb_under_panic: 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: ipv6_addrconf addrconf_dad_work RIP: 0010:skb_panic+0x152/0x1d0 Call Trace: <TASK> skb_push+0xc4/0xe0 ip6mr_cache_report+0xd69/0x19b0 reg_vif_xmit+0x406/0x690 dev_hard_start_xmit+0x17e/0x6e0 __dev_queue_xmit+0x2d6a/0x3d20 vlan_dev_hard_start_xmit+0x3ab/0x5c0 dev_hard_start_xmit+0x17e/0x6e0 __dev_queue_xmit+0x2d6a/0x3d20 neigh_connected_output+0x3ed/0x570 ip6_finish_output2+0x5b5/0x1950 ip6_finish_output+0x693/0x11c0 ip6_output+0x24b/0x880 NF_HOOK.constprop.0+0xfd/0x530 ndisc_send_skb+0x9db/0x1400 ndisc_send_rs+0x12a/0x6c0 addrconf_dad_completed+0x3c9/0xea0 addrconf_dad_work+0x849/0x1420 process_one_work+0xa22/0x16e0 worker_thread+0x679/0x10c0 ret_from_fork+0x28/0x60 ret_from_fork_asm+0x11/0x20 When setup a vlan device on dev pim6reg, DAD ns packet may sent on reg_vif_xmit(). reg_vif_xmit() ip6mr_cache_report() skb_push(skb, -skb_network_offset(pkt));//skb_network_offset(pkt) is 4 And skb_push declared as: void *skb_push(struct sk_buff *skb, unsigned int len); skb->data -= len; //0xffff88805f86a84c - 0xfffffffc = 0xffff887f5f86a850 skb->data is set to 0xffff887f5f86a850, which is invalid mem addr, lead to skb_push() fails.

#	Date	Old EPSS score	New EPSS score	Delta (New - Old)
1	2025-09-18	—	0.02%	—

Date

Old EPSS score

New EPSS score

Delta (New - Old)

2025-09-18

—

0.02%

—

Base score	Version	Severity	Vector	Exploitability	Impact	Score source
5.5	3.1	MEDIUM	`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H` Click to expand Attack vector (AV:L) They already need access on the box, or another person has to do something wrong; it’s not a remote drive-by. Attack complexity (AC:L) Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup. Privileges required (PR:L) A normal user session is enough; they don’t have to be admin. User interaction (UI:N) Nobody has to click “OK” or open a trap file; it can work without a victim helping. Scope (S:U) Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems. Confidentiality (C:N) Doesn’t really leak secrets in a meaningful way. Integrity (I:N) Data isn’t meaningfully altered or forged. Availability (A:H) Could take the service down hard or make it unusable for people who depend on it.	1.8	3.6	[email protected]
5.5	3.1	MEDIUM	`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H` Click to expand Attack vector (AV:L) They already need access on the box, or another person has to do something wrong; it’s not a remote drive-by. Attack complexity (AC:L) Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup. Privileges required (PR:L) A normal user session is enough; they don’t have to be admin. User interaction (UI:N) Nobody has to click “OK” or open a trap file; it can work without a victim helping. Scope (S:U) Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems. Confidentiality (C:N) Doesn’t really leak secrets in a meaningful way. Integrity (I:N) Data isn’t meaningfully altered or forged. Availability (A:H) Could take the service down hard or make it unusable for people who depend on it.	1.8	3.6	134c704f-9b21-4f2e-91b3-4a467353bcc0

Base score

Version

Severity

Vector

Exploitability

Impact

Score source

5.5

3.1

MEDIUM

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H Click to expand

Attack vector (AV:L): They already need access on the box, or another person has to do something wrong; it’s not a remote drive-by.
Attack complexity (AC:L): Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:L): A normal user session is enough; they don’t have to be admin.
User interaction (UI:N): Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U): Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N): Doesn’t really leak secrets in a meaningful way.
Integrity (I:N): Data isn’t meaningfully altered or forged.
Availability (A:H): Could take the service down hard or make it unusable for people who depend on it.

1.8

3.6

[email protected]

5.5

3.1

MEDIUM

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H Click to expand

Attack vector (AV:L): They already need access on the box, or another person has to do something wrong; it’s not a remote drive-by.
Attack complexity (AC:L): Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:L): A normal user session is enough; they don’t have to be admin.
User interaction (UI:N): Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U): Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N): Doesn’t really leak secrets in a meaningful way.
Integrity (I:N): Data isn’t meaningfully altered or forged.
Availability (A:H): Could take the service down hard or make it unusable for people who depend on it.

1.8

3.6

134c704f-9b21-4f2e-91b3-4a467353bcc0

OS Trackers for CVE-2023-53365

vendor	priority	summary	link
`debian`	not yet assigned	CVE-2023-53365 not yet assigned priority: Debian including 1 source packages (linux), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5.	https://security-tracker.debian.org/tracker/CVE-2023-53365
`redhat`	medium	—	https://access.redhat.com/security/cve/CVE-2023-53365
`suse`	medium	—	https://www.suse.com/security/cve/CVE-2023-53365/
`ubuntu`	medium	CVE-2023-53365 medium priority: Ubuntu including 158 source packages (linux, linux-allwinner-5.19, …), 1414 status rows across 9 suites (bionic, focal, jammy, noble, plucky, questing, trusty, upstream, xenial): DNE 1017, ignored 162, released 138, not-affected 77, needed 19, needs-triage 1.	https://ubuntu.com/security/CVE-2023-53365

Affected software / configurations for CVE-2023-53365

Vendor	Product	Version	Raw CPE
linux	linux_kernel	>= 2.6.26, < 4.14.322	cpe:2.3:o:linux:linux_kernel::::::::
linux	linux_kernel	>= 4.15, < 4.19.291	cpe:2.3:o:linux:linux_kernel::::::::
linux	linux_kernel	>= 4.20, < 5.4.253	cpe:2.3:o:linux:linux_kernel::::::::
linux	linux_kernel	>= 5.5, < 5.10.190	cpe:2.3:o:linux:linux_kernel::::::::
linux	linux_kernel	>= 5.11, < 5.15.126	cpe:2.3:o:linux:linux_kernel::::::::
linux	linux_kernel	>= 5.16, < 6.1.45	cpe:2.3:o:linux:linux_kernel::::::::
linux	linux_kernel	>= 6.2, < 6.4.10	cpe:2.3:o:linux:linux_kernel::::::::
linux	linux_kernel	6.5	cpe:2.3:o:linux:linux_kernel:6.5:rc1::::::
linux	linux_kernel	6.5	cpe:2.3:o:linux:linux_kernel:6.5:rc2::::::
linux	linux_kernel	6.5	cpe:2.3:o:linux:linux_kernel:6.5:rc3::::::
linux	linux_kernel	6.5	cpe:2.3:o:linux:linux_kernel:6.5:rc4::::::

References for CVE-2023-53365

URL	Tags
https://git.kernel.org/stable/c/0438e60a00d4e335b3c36397dbf26c74b5d13ef0	Patch
https://git.kernel.org/stable/c/1683124129a4263dd5bce2475bab110e95fa0346	Patch
https://git.kernel.org/stable/c/1bb54a21f4d9b88442f8c3307c780e2db64417e4	Patch
https://git.kernel.org/stable/c/30e0191b16e8a58e4620fa3e2839ddc7b9d4281c	Patch
https://git.kernel.org/stable/c/3326c711f18d18fe6e1f5d83d3a7eab07e5a1560	Patch
https://git.kernel.org/stable/c/691a09eecad97e745b9aa0e3918db46d020bdacb	Patch
https://git.kernel.org/stable/c/8382e7ed2d63e6c2daf6881fa091526dc6c879cd	Patch
https://git.kernel.org/stable/c/a96d74d1076c82a4cef02c150d9996b21354c78d	Patch

URL

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

Exploit prediction scoring system (EPSS) score for CVE-2023-53365

Common vulnerability scoring system (CVSS) metrics for CVE-2023-53365

Weakness enumeration for CVE-2023-53365

OS Trackers for CVE-2023-53365

Affected software / configurations for CVE-2023-53365

References for CVE-2023-53365