7.5

CVE-2021-46983: nvmet-rdma: Fix NULL deref when SEND is completed with error

Modified
AliasesUBUNTU-CVE-2021-46983DEBIAN-CVE-2021-46983
Published 28-02-2024Last modified 05-08-2026

Vulnerability summary

CVE-2021-46983 is a high (CVSS 7.5) NULL Pointer Dereference vulnerability in linux. EPSS estimates a 0.63% chance of exploitation in the next 30 days, higher than 50.3% of scored vulnerabilities.

Priority
Prioritisesevere

Severe, CVSS 7.5 (CVE.org); no exploitation reported by the 5 checked sources; EPSS 1% (FIRST, 03-11-2026)

Source freshness unavailable

How is this decided?
CVSS score
7.5/10
010
High · v3.1 (CVE.org)
EPSS score
0.63%
0%100%
Low · 0.00 pp in 30 days
KEVNot listedNot listed by any tracked catalog.
RansomwareNot flaggedNo ransomware use recorded.
Public exploits0No public exploits recorded

Advisory lineage

Upstream 0 · Downstream 3 · Related 2
RHSA-2021:4356SUSE-SU-2024:1465-1SUSE-SU-2024:1489-1

Timeline

  1. 28-02-2024
    PublishedVulnerability first disclosed.
  2. 05-08-2026
    Last modifiedVulnerability information updated.

Description

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 The cq_context is no longer valid after the fix to use shared CQ mechanism and should be obtained similar to how it is obtained in other functions from the wc-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

CVSS metrics

4 scores · 4 sources · 1 version

EPSS trend

Probability

0.63%

Chance of exploitation in the next 30 days

Percentile

50%

Versus all other CVEs

30-day change

No change 0.00 pp

From 0.63% on 04-10-2026

04-10-202603-11-2026

Known exploited

Compare KEV catalogs
CISA KEV

Not in the CISA KEV catalog.

ENISA CNW

Not in the ENISA CNW catalog.

CIRCL

Not in the CIRCL catalog.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

Version check

Known conditions: network-reachable, no authentication, no user interaction (CVSS vector). Other conditions: not stated in public data.

Ubuntu62 products
  • linux-allwinner-5.19All versions (No fix recorded)
  • linux-aws-5.0All versions (No fix recorded)
  • linux-aws-5.11All versions (No fix recorded)
  • linux-aws-5.13All versions (No fix recorded)
  • linux-aws-5.19All versions (No fix recorded)
Linux2 products
  • linux≥ ca0f1a8055be2a04073af435dc68419334481638, < 64f3410c7bfc389b1a58611d0799f4a36ce4b6b5 | ≥ ca0f1a8055be2a04073af435dc68419334481638, < 17fb6dfa5162b89ecfa07df891a53afec321abe8 | ≥ ca0f1a8055be2a04073af435dc68419334481638, < 5bdb34466ad8370546dfa0497594fb1d6f2fed90 | ≥ ca0f1a8055be2a04073af435dc68419334481638, < 8cc365f9559b86802afc0208389f5c8d46b4ad61 | 5.9
  • linux_kernel≥ 5.9, < 5.10.38 | ≥ 5.11, < 5.11.22 | ≥ 5.12, < 5.12.5 | 5.13:rc1
Debian1 product
  • linux< 5.10.38-1

3 vendors · 65 products

References

8 links