CVE-2022-49904 [Medium] | Security Vulnerability in Linux Kernel

In the Linux kernel, the following vulnerability has been resolved: net, neigh: Fix null-ptr-deref in neigh_table_clear() When IPv6 module gets initialized but hits an error in the middle, kenel panic with: KASAN: null-ptr-deref in range [0x0000000000000598-0x000000000000059f] CPU: 1 PID: 361 Comm: insmod Hardware name: QEMU Standard PC (i440FX + PIIX, 1996) RIP: 0010:__neigh_ifdown.isra.0+0x24b/0x370 RSP: 0018:ffff888012677908 EFLAGS: 00000202 ... Call Trace: <TASK> neigh_table_clear+0x94/0x2d0 ndisc_cleanup+0x27/0x40 [ipv6] inet6_init+0x21c/0x2cb [ipv6] do_one_initcall+0xd3/0x4d0 do_init_module+0x1ae/0x670 ... Kernel panic - not syncing: Fatal exception When ipv6 initialization fails, it will try to cleanup and calls: neigh_table_clear() neigh_ifdown(tbl, NULL) pneigh_queue_purge(&tbl->proxy_queue, dev_net(dev == NULL)) # dev_net(NULL) triggers null-ptr-deref. Fix it by passing NULL to pneigh_queue_purge() in neigh_ifdown() if dev is NULL, to make kernel not panic immediately.

#	Date	Old EPSS score	New EPSS score	Delta (New - Old)
1	2026-06-09	0.06%	0.02%	-0.04%
2	2026-02-25	0.02%	0.06%	+0.04%
3	2025-05-02	—	0.02%	—

Date

Old EPSS score

New EPSS score

Delta (New - Old)

2026-06-09

0.06%

0.02%

-0.04%

2026-02-25

0.02%

0.06%

+0.04%

2025-05-02

—

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-2022-49904

vendor	priority	summary	link
`debian`	not yet assigned	CVE-2022-49904 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-2022-49904
`redhat`	medium	—	https://access.redhat.com/security/cve/CVE-2022-49904
`suse`	medium	CVE-2022-49904 severity moderate: SUSE including 26 source package names (cluster-md-kmp-default, dlm-kmp-default, …), 264 product×package rows across 51 product lines (SLES-LTSS-TERADATA 15 SP2, SUSE Linux Enterprise High Availability Extension 15 SP7, … (51 product lines)): Known Not Affected 264.	https://www.suse.com/security/cve/CVE-2022-49904/
`ubuntu`	medium	CVE-2022-49904 medium priority: Ubuntu including 158 source packages (linux, linux-allwinner-5.19, …), 1551 status rows across 10 suites (bionic, focal, jammy, noble, oracular, plucky, questing, trusty, upstream, xenial): DNE 1145, released 152, ignored 146, not-affected 107, needs-triage 1.	https://ubuntu.com/security/CVE-2022-49904

Affected software / configurations for CVE-2022-49904

Vendor	Product	Version	Raw CPE
linux	linux_kernel	>= 4.14.292, < 4.14.299	cpe:2.3:o:linux:linux_kernel::::::::
linux	linux_kernel	>= 4.19.257, < 4.19.265	cpe:2.3:o:linux:linux_kernel::::::::
linux	linux_kernel	>= 5.4.212, < 5.4.224	cpe:2.3:o:linux:linux_kernel::::::::
linux	linux_kernel	>= 5.10.141, < 5.10.154	cpe:2.3:o:linux:linux_kernel::::::::
linux	linux_kernel	>= 5.15.65, < 5.15.78	cpe:2.3:o:linux:linux_kernel::::::::
linux	linux_kernel	>= 5.19.7, < 6.0.8	cpe:2.3:o:linux:linux_kernel::::::::
linux	linux_kernel	6.1	cpe:2.3:o:linux:linux_kernel:6.1:rc1::::::
linux	linux_kernel	6.1	cpe:2.3:o:linux:linux_kernel:6.1:rc2::::::
linux	linux_kernel	6.1	cpe:2.3:o:linux:linux_kernel:6.1:rc3::::::

References for CVE-2022-49904

URL	Tags
https://git.kernel.org/stable/c/0d38b4ca6679e72860ff8730e79bb99d0e9fa3b0	Patch
https://git.kernel.org/stable/c/1c89642e7f2b7ecc9635610653f5c2f0276c0051	Patch
https://git.kernel.org/stable/c/2b45d6d0c41cb9593868e476681efb1aae5078a1	Patch
https://git.kernel.org/stable/c/a99a8ec4c62180c889482a2ff6465033e0743458	Patch
https://git.kernel.org/stable/c/b49f6b2f21f543d4dc88fb7b1ec2adccb822f27c	Patch
https://git.kernel.org/stable/c/b736592de2aa53aee2d48d6b129bc0c892007bbe	Patch
https://git.kernel.org/stable/c/f8017317cb0b279b8ab98b0f3901a2e0ac880dad	Patch

URL

CVE-2022-49904 | net, neigh: Fix null-ptr-deref in neigh_table_clear()

Exploit prediction scoring system (EPSS) score for CVE-2022-49904

Common vulnerability scoring system (CVSS) metrics for CVE-2022-49904

Weakness enumeration for CVE-2022-49904

OS Trackers for CVE-2022-49904

Affected software / configurations for CVE-2022-49904

References for CVE-2022-49904