What is CVE-2021-47536?

CVE-2021-47536 is a High severity Linux kernel vulnerability with a CVSS score of 7.8 out of 10, classified as a Out-of-bounds Write flaw (CWE-787). CVE-2021-47536 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

What is the CVSS score for CVE-2021-47536?

CVE-2021-47536 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-2021-47536?

No patch is currently available for CVE-2021-47536. Monitor the NIST NVD and your Linux distribution's security advisories for updates.

Is CVE-2021-47536 actively exploited?

CVE-2021-47536 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

What is Out-of-bounds Write (CWE-787)?

The product writes data past the end or before the beginning of the intended buffer. See MITRE CWE for full details: https://cwe.mitre.org/data/definitions/787.html

CVE-2021-47536

High

In the Linux kernel, the following vulnerability has been resolved: net/smc: fix wrong list_del in smc_lgr_cleanup_early smc_lgr_cleanup_early() meant to delete the link group from the link group list, but it deleted the list head by mistake. This may cause memory corruption since we didn't remove the real link group from the list and later memseted the link group structure. We got a list corruption panic when testing: [ 231.277259] list_del corruption. prev->next should be ffff8881398a8000, but was 0000000000000000 [ 231.278222] ------------[ cut here ]------------ [ 231.278726] kernel BUG at lib/list_debug.c:53! [ 231.279326] invalid opcode: 0000 [#1] SMP NOPTI [ 231.279803] CPU: 0 PID: 5 Comm: kworker/0:0 Not tainted 5.10.46+ #435 [ 231.280466] Hardware name: Alibaba Cloud ECS, BIOS 8c24b4c 04/01/2014 [ 231.281248] Workqueue: events smc_link_down_work [ 231.281732] RIP: 0010:__list_del_entry_valid+0x70/0x90 [ 231.282258] Code: 4c 60 82 e8 7d cc 6a 00 0f 0b 48 89 fe 48 c7 c7 88 4c 60 82 e8 6c cc 6a 00 0f 0b 48 89 fe 48 c7 c7 c0 4c 60 82 e8 5b cc 6a 00 <0f> 0b 48 89 fe 48 c7 c7 00 4d 60 82 e8 4a cc 6a 00 0f 0b cc cc cc [ 231.284146] RSP: 0018:ffffc90000033d58 EFLAGS: 00010292 [ 231.284685] RAX: 0000000000000054 RBX: ffff8881398a8000 RCX: 0000000000000000 [ 231.285415] RDX: 0000000000000001 RSI: ffff88813bc18040 RDI: ffff88813bc18040 [ 231.286141] RBP: ffffffff8305ad40 R08: 0000000000000003 R09: 0000000000000001 [ 231.286873] R10: ffffffff82803da0 R11: ffffc90000033b90 R12: 0000000000000001 [ 231.287606] R13: 0000000000000000 R14: ffff8881398a8000 R15: 0000000000000003 [ 231.288337] FS: 0000000000000000(0000) GS:ffff88813bc00000(0000) knlGS:0000000000000000 [ 231.289160] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 231.289754] CR2: 0000000000e72058 CR3: 000000010fa96006 CR4: 00000000003706f0 [ 231.290485] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 231.291211] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 231.291940] Call Trace: [ 231.292211] smc_lgr_terminate_sched+0x53/0xa0 [ 231.292677] smc_switch_conns+0x75/0x6b0 [ 231.293085] ? update_load_avg+0x1a6/0x590 [ 231.293517] ? ttwu_do_wakeup+0x17/0x150 [ 231.293907] ? update_load_avg+0x1a6/0x590 [ 231.294317] ? newidle_balance+0xca/0x3d0 [ 231.294716] smcr_link_down+0x50/0x1a0 [ 231.295090] ? __wake_up_common_lock+0x77/0x90 [ 231.295534] smc_link_down_work+0x46/0x60 [ 231.295933] process_one_work+0x18b/0x350

Package Linux Kernel

Published 2024-05-24

Last modified 2025-09-18

CVSS version 3.1

Patch available

Awaiting data

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-787

CVE-2021-47536 is a Out-of-bounds Write vulnerability

What is Out-of-bounds Write?

The product writes data past the end or before the beginning of the intended buffer. Learn more on MITRE CWE

References

The following references provide additional information about CVE-2021-47536 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/77731fede297a23d26f2d169b4269466b2c82529
Patch
Kernel patch commit
https://git.kernel.org/stable/c/789b6cc2a5f9123b9c549b886fdc47c865cfe0ba
Patch
Kernel patch commit
https://git.kernel.org/stable/c/95518fe354d712dca6f431cf2a11b8f63bc9a66c
Patch

Details

CVE ID CVE-2021-47536

Severity High

CVSS score 7.8 / 10

CVSS version 3.1

Published 2024-05-24

Modified 2025-09-18

KEV No

Patch Awaiting data

Package linux

Frequently asked questions

What is CVE-2021-47536?

CVE-2021-47536 is a High severity Linux kernel vulnerability with a CVSS score of 7.8 out of 10 , classified as an Out-of-bounds Write flaw (CWE-787) . CVE-2021-47536 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.
What is the CVSS score for CVE-2021-47536?

CVE-2021-47536 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-2021-47536?

No patch is currently available for CVE-2021-47536. Monitor the NIST NVD and your Linux distribution's security advisories for updates.
Is CVE-2021-47536 actively exploited?

No — CVE-2021-47536 has not been confirmed as actively exploited. It is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.
What is Out-of-bounds Write (CWE-787)?

The product writes data past the end or before the beginning of the intended buffer. View CWE-787 on MITRE CWE →