What is CVE-2021-46983?

CVE-2021-46983 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). CVE-2021-46983 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

What is the CVSS score for CVE-2021-46983?

CVE-2021-46983 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-2021-46983?

No patch is currently available for CVE-2021-46983. Monitor the NIST NVD and your Linux distribution's security advisories for updates.

Is CVE-2021-46983 actively exploited?

CVE-2021-46983 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-2021-46983

Medium

In the Linux kernel, the following vulnerability has been resolved: nvmet-rdma: Fix NULL deref when SEND is completed with error When running some traffic and taking down the link on peer, a retry counter exceeded error is received. This leads to nvmet_rdma_error_comp which tried accessing the cq_context to obtain the queue. The cq_context is no longer valid after the fix to use shared CQ mechanism and should be obtained similar to how it is obtained in other functions from the wc->qp. [ 905.786331] nvmet_rdma: SEND for CQE 0x00000000e3337f90 failed with status transport retry counter exceeded (12). [ 905.832048] BUG: unable to handle kernel NULL pointer dereference at 0000000000000048 [ 905.839919] PGD 0 P4D 0 [ 905.842464] Oops: 0000 1 SMP NOPTI [ 905.846144] CPU: 13 PID: 1557 Comm: kworker/13:1H Kdump: loaded Tainted: G OE --------- - - 4.18.0-304.el8.x86_64 #1 [ 905.872135] RIP: 0010:nvmet_rdma_error_comp+0x5/0x1b [nvmet_rdma] [ 905.878259] Code: 19 4f c0 e8 89 b3 a5 f6 e9 5b e0 ff ff 0f b7 75 14 4c 89 ea 48 c7 c7 08 1a 4f c0 e8 71 b3 a5 f6 e9 4b e0 ff ff 0f 1f 44 00 00 <48> 8b 47 48 48 85 c0 74 08 48 89 c7 e9 98 bf 49 00 e9 c3 e3 ff ff [ 905.897135] RSP: 0018:ffffab601c45fe28 EFLAGS: 00010246 [ 905.902387] RAX: 0000000000000065 RBX: ffff9e729ea2f800 RCX: 0000000000000000 [ 905.909558] RDX: 0000000000000000 RSI: ffff9e72df9567c8 RDI: 0000000000000000 [ 905.916731] RBP: ffff9e729ea2b400 R08: 000000000000074d R09: 0000000000000074 [ 905.923903] R10: 0000000000000000 R11: ffffab601c45fcc0 R12: 0000000000000010 [ 905.931074] R13: 0000000000000000 R14: 0000000000000010 R15: ffff9e729ea2f400 [ 905.938247] FS: 0000000000000000(0000) GS:ffff9e72df940000(0000) knlGS:0000000000000000 [ 905.938249] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 905.950067] nvmet_rdma: SEND for CQE 0x00000000c7356cca failed with status transport retry counter exceeded (12). [ 905.961855] CR2: 0000000000000048 CR3: 000000678d010004 CR4: 00000000007706e0 [ 905.961855] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 905.961856] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 905.961857] PKRU: 55555554 [ 906.010315] Call Trace: [ 906.012778] __ib_process_cq+0x89/0x170 [ib_core] [ 906.017509] ib_cq_poll_work+0x26/0x80 [ib_core] [ 906.022152] process_one_work+0x1a7/0x360 [ 906.026182] ? create_worker+0x1a0/0x1a0 [ 906.030123] worker_thread+0x30/0x390 [ 906.033802] ? create_worker+0x1a0/0x1a0 [ 906.037744] kthread+0x116/0x130 [ 906.040988] ? kthread_flush_work_fn+0x10/0x10 [ 906.045456] ret_from_fork+0x1f/0x40

Package Linux Kernel

Published 2024-02-28

Last modified 2024-12-06

CVSS version 3.1

Patch available

Awaiting data

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-2021-46983 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

References

The following references provide additional information about CVE-2021-46983 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/17fb6dfa5162b89ecfa07df891a53afec321abe8
Patch
Kernel patch commit
https://git.kernel.org/stable/c/5bdb34466ad8370546dfa0497594fb1d6f2fed90
Patch
Kernel patch commit
https://git.kernel.org/stable/c/64f3410c7bfc389b1a58611d0799f4a36ce4b6b5
Patch

4 patch commits total View all on NVD

Details

CVE ID CVE-2021-46983

Severity Medium

CVSS score 5.5 / 10

CVSS version 3.1

Published 2024-02-28

Modified 2024-12-06

KEV No

Patch Awaiting data

Package linux

Frequently asked questions

What is CVE-2021-46983?

CVE-2021-46983 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) . CVE-2021-46983 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.
What is the CVSS score for CVE-2021-46983?

CVE-2021-46983 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-2021-46983?

No patch is currently available for CVE-2021-46983. Monitor the NIST NVD and your Linux distribution's security advisories for updates.
Is CVE-2021-46983 actively exploited?

No — CVE-2021-46983 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 →