What is CVE-2022-49649?

CVE-2022-49649 is a Medium severity Linux kernel vulnerability with a CVSS score of 5.5 out of 10, classified as a NULL Pointer Dereference flaw (CWE-476), affecting Linux kernel versions from 4.9 onward and patched in 4.9.324, 4.14.289, 4.19.253 and others. CVE-2022-49649 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

What is the CVSS score for CVE-2022-49649?

CVE-2022-49649 has a CVSS score of 5.5 out of 10, rated Medium severity. 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-2022-49649?

Yes, CVE-2022-49649 has been patched. Fixed versions include 4.9.324, 4.14.289, 4.19.253 and others. If you are running Linux kernel 4.9 or later up to the fix versions, apply the relevant patch for your kernel branch.

Is CVE-2022-49649 actively exploited?

CVE-2022-49649 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

What is NULL Pointer Dereference (CWE-476)?

The product dereferences a pointer that it expects to be valid but is NULL, typically causing a crash. See MITRE CWE for full details: https://cwe.mitre.org/data/definitions/476.html

CVE-2022-49649

Medium

In the Linux kernel, the following vulnerability has been resolved: xen/netback: avoid entering xenvif_rx_next_skb() with an empty rx queue xenvif_rx_next_skb() is expecting the rx queue not being empty, but in case the loop in xenvif_rx_action() is doing multiple iterations, the availability of another skb in the rx queue is not being checked. This can lead to crashes: [40072.537261] BUG: unable to handle kernel NULL pointer dereference at 0000000000000080 [40072.537407] IP: xenvif_rx_skb+0x23/0x590 [xen_netback] [40072.537534] PGD 0 P4D 0 [40072.537644] Oops: 0000 [#1] SMP NOPTI [40072.537749] CPU: 0 PID: 12505 Comm: v1-c40247-q2-gu Not tainted 4.12.14-122.121-default #1 SLE12-SP5 [40072.537867] Hardware name: HP ProLiant DL580 Gen9/ProLiant DL580 Gen9, BIOS U17 11/23/2021 [40072.537999] task: ffff880433b38100 task.stack: ffffc90043d40000 [40072.538112] RIP: e030:xenvif_rx_skb+0x23/0x590 [xen_netback] [40072.538217] RSP: e02b:ffffc90043d43de0 EFLAGS: 00010246 [40072.538319] RAX: 0000000000000000 RBX: ffffc90043cd7cd0 RCX: 00000000000000f7 [40072.538430] RDX: 0000000000000000 RSI: 0000000000000006 RDI: ffffc90043d43df8 [40072.538531] RBP: 000000000000003f R08: 000077ff80000000 R09: 0000000000000008 [40072.538644] R10: 0000000000007ff0 R11: 00000000000008f6 R12: ffffc90043ce2708 [40072.538745] R13: 0000000000000000 R14: ffffc90043d43ed0 R15: ffff88043ea748c0 [40072.538861] FS: 0000000000000000(0000) GS:ffff880484600000(0000) knlGS:0000000000000000 [40072.538988] CS: e033 DS: 0000 ES: 0000 CR0: 0000000080050033 [40072.539088] CR2: 0000000000000080 CR3: 0000000407ac8000 CR4: 0000000000040660 [40072.539211] Call Trace: [40072.539319] xenvif_rx_action+0x71/0x90 [xen_netback] [40072.539429] xenvif_kthread_guest_rx+0x14a/0x29c [xen_netback] Fix that by stopping the loop in case the rx queue becomes empty.

Package Linux Kernel

Published 2025-02-26

Last modified 2025-10-01

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-476

CVE-2022-49649 is a NULL Pointer Dereference vulnerability

What is NULL Pointer Dereference?

The product dereferences a pointer that it expects to be valid but is NULL, typically causing a crash. Learn more on MITRE CWE

Affected versions

Linux kernel versions 4.9 and later are affected. Fixed in 4.9.324, 4.14.289, 4.19.253, 5.4.207, 5.10.132, 5.15.56, 5.18.13, 5.19 and their respective stable series.

Affected from

≥ 4.9

Fixed in

✓ 4.9.324 4.9.x ✓ 4.14.289 4.14.x ✓ 4.19.253 4.19.x ✓ 5.4.207 5.4.x ✓ 5.10.132 5.10.x ✓ 5.15.56 5.15.x ✓ 5.18.13 5.18.x ✓ 5.19

References

The following references provide additional information about CVE-2022-49649 including vendor advisories, patch commits, exploit details, and third-party analysis. Links are sourced from the NIST NVD database.

Kernel patch commit
https://git.kernel.org/stable/c/5a071aefd6414af5a20321ab58a0557b81993687
Patch
Kernel patch commit
https://git.kernel.org/stable/c/7425479d20f9e96f7c3ec8e8a93fe0d7478724cb
Patch
Kernel patch commit
https://git.kernel.org/stable/c/94e8100678889ab428e68acadf042de723f094b9
Patch

8 patch commits total View all on NVD

Details

CVE ID CVE-2022-49649

Severity Medium

CVSS score 5.5 / 10

CVSS version 3.1

Published 2025-02-26

Modified 2025-10-01

KEV No

Patch

Yes

Package linux

Frequently asked questions

What is CVE-2022-49649?

CVE-2022-49649 is a Medium severity Linux kernel vulnerability with a CVSS score of 5.5 out of 10 , classified as a NULL Pointer Dereference flaw (CWE-476) . It affects Linux kernel versions from 4.9 onward and has been patched in 4.9.324, 4.14.289, 4.19.253 and others. CVE-2022-49649 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.
What is the CVSS score for CVE-2022-49649?

CVE-2022-49649 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-2022-49649?

Yes — CVE-2022-49649 has been patched. Fixed versions include 4.9.324, 4.14.289, 4.19.253 and others. If you are running Linux kernel 4.9 or later up to the fix versions, apply the relevant patch for your kernel branch.
Is CVE-2022-49649 actively exploited?

No — CVE-2022-49649 has not been confirmed as actively exploited. It is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.
What is NULL Pointer Dereference (CWE-476)?

The product dereferences a pointer that it expects to be valid but is NULL, typically causing a crash. View CWE-476 on MITRE CWE →