What is CVE-2021-47196?

CVE-2021-47196 is a High severity Linux kernel vulnerability with a CVSS score of 7.8 out of 10, classified as a Use After Free flaw (CWE-416), affecting Linux kernel versions from 5.15 onward and patched in 5.15.5 and 5.16. CVE-2021-47196 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

What is the CVSS score for CVE-2021-47196?

CVE-2021-47196 has a CVSS score of 7.8 out of 10, rated High severity. The vector string is CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.

Is there a patch available for CVE-2021-47196?

Yes, CVE-2021-47196 has been patched. Fixed versions include 5.15.5 and 5.16. If you are running Linux kernel 5.15 or later up to the fix versions, apply the relevant patch for your kernel branch.

Is CVE-2021-47196 actively exploited?

CVE-2021-47196 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

What is Use After Free (CWE-416)?

The product references memory after it has been freed, which may cause it to crash, use unexpected values, or execute code. See MITRE CWE for full details: https://cwe.mitre.org/data/definitions/416.html

CVE-2021-47196

High

In the Linux kernel, the following vulnerability has been resolved: RDMA/core: Set send and receive CQ before forwarding to the driver Preset both receive and send CQ pointers prior to call to the drivers and overwrite it later again till the mlx4 is going to be changed do not overwrite ibqp properties. This change is needed for mlx5, because in case of QP creation failure, it will go to the path of QP destroy which relies on proper CQ pointers. BUG: KASAN: use-after-free in create_qp.cold+0x164/0x16e [mlx5_ib] Write of size 8 at addr ffff8880064c55c0 by task a.out/246 CPU: 0 PID: 246 Comm: a.out Not tainted 5.15.0+ #291 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014 Call Trace: dump_stack_lvl+0x45/0x59 print_address_description.constprop.0+0x1f/0x140 kasan_report.cold+0x83/0xdf create_qp.cold+0x164/0x16e [mlx5_ib] mlx5_ib_create_qp+0x358/0x28a0 [mlx5_ib] create_qp.part.0+0x45b/0x6a0 [ib_core] ib_create_qp_user+0x97/0x150 [ib_core] ib_uverbs_handler_UVERBS_METHOD_QP_CREATE+0x92c/0x1250 [ib_uverbs] ib_uverbs_cmd_verbs+0x1c38/0x3150 [ib_uverbs] ib_uverbs_ioctl+0x169/0x260 [ib_uverbs] __x64_sys_ioctl+0x866/0x14d0 do_syscall_64+0x3d/0x90 entry_SYSCALL_64_after_hwframe+0x44/0xae Allocated by task 246: kasan_save_stack+0x1b/0x40 __kasan_kmalloc+0xa4/0xd0 create_qp.part.0+0x92/0x6a0 [ib_core] ib_create_qp_user+0x97/0x150 [ib_core] ib_uverbs_handler_UVERBS_METHOD_QP_CREATE+0x92c/0x1250 [ib_uverbs] ib_uverbs_cmd_verbs+0x1c38/0x3150 [ib_uverbs] ib_uverbs_ioctl+0x169/0x260 [ib_uverbs] __x64_sys_ioctl+0x866/0x14d0 do_syscall_64+0x3d/0x90 entry_SYSCALL_64_after_hwframe+0x44/0xae Freed by task 246: kasan_save_stack+0x1b/0x40 kasan_set_track+0x1c/0x30 kasan_set_free_info+0x20/0x30 __kasan_slab_free+0x10c/0x150 slab_free_freelist_hook+0xb4/0x1b0 kfree+0xe7/0x2a0 create_qp.part.0+0x52b/0x6a0 [ib_core] ib_create_qp_user+0x97/0x150 [ib_core] ib_uverbs_handler_UVERBS_METHOD_QP_CREATE+0x92c/0x1250 [ib_uverbs] ib_uverbs_cmd_verbs+0x1c38/0x3150 [ib_uverbs] ib_uverbs_ioctl+0x169/0x260 [ib_uverbs] __x64_sys_ioctl+0x866/0x14d0 do_syscall_64+0x3d/0x90 entry_SYSCALL_64_after_hwframe+0x44/0xae

Package Linux Kernel

Published 2024-04-10

Last modified 2025-03-04

CVSS version 3.1

Patch available

Yes

CVSS 3.1 score

7.8

out of 10

High

Attack Vector

Local

Attack Complexity

Low

Privileges Required

Low

User Interaction

None

Scope

Unchanged

Confidentiality

High

Integrity

High

Availability

High

Vector string

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

Weakness type

CWE-416

CVE-2021-47196 is a Use After Free vulnerability

What is Use After Free?

The product references memory after it has been freed, which may cause it to crash, use unexpected values, or execute code. Learn more on MITRE CWE

Affected versions

Linux kernel versions 5.15 and later are affected. Fixed in 5.15.5, 5.16 and their respective stable series.

Affected from

≥ 5.15

Fixed in

✓ 5.15.5 5.15.x ✓ 5.16

References

2 total

Kernel Git
https://git.kernel.org/stable/c/6cd7397d01c4a3e09757840299e4f114f0aa5fa0

Mailing List Patch
Kernel Git
https://git.kernel.org/stable/c/b70e072feffa0ba5c41a99b9524b9878dee7748e

Mailing List Patch

Details

CVE ID CVE-2021-47196

Severity High

CVSS score 7.8 / 10

CVSS version 3.1

Published 2024-04-10

Modified 2025-03-04

KEV No

Patch

Yes

Package linux

Frequently asked questions

What is CVE-2021-47196?

CVE-2021-47196 is a High severity Linux kernel vulnerability with a CVSS score of 7.8 out of 10 , classified as an Use After Free flaw (CWE-416) . It affects Linux kernel versions from 5.15 onward and has been patched in 5.15.5 and 5.16. CVE-2021-47196 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.
What is the CVSS score for CVE-2021-47196?

CVE-2021-47196 has a CVSS score of 7.8 out of 10, rated High severity (CVSS 3.1). The vector string is CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.
Is there a patch available for CVE-2021-47196?

Yes. CVE-2021-47196 has been patched. Fixed versions include 5.15.5 and 5.16. If you are running Linux kernel 5.15 or later up to the fix versions, apply the relevant patch for your kernel branch.
Is CVE-2021-47196 actively exploited?

No. CVE-2021-47196 has not been confirmed as actively exploited. It is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.