CVE-2026-43120: In the Linux kernel, the following vulnerability has been resolved: RDMA/irdma: Fix double free related to rereg_user_mr If IB_MR_REREG_TRANS is set...

Description

In the Linux kernel, the following vulnerability has been resolved: RDMA/irdma: Fix double free related to rereg_user_mr If IB_MR_REREG_TRANS is set during rereg_user_mr, the umem will be released and a new one will be allocated in irdma_rereg_mr_trans. If any step of irdma_rereg_mr_trans fails after the new umem is allocated, it releases the umem, but does not set iwmr->region to NULL. The problem is that this failure is propagated to the user, who will then call ibv_dereg_mr (as they should). Then, the dereg_mr path will see a non-NULL umem and attempt to call ib_umem_release again. Fix this by setting iwmr->region to NULL after ib_umem_release. Fixed: 5ac388db27c4 ("RDMA/irdma: Add support to re-register a memory region")

Metrics

CVSS 3.1

7.8/10

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

EPSS Probability

0.12%

2.3th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-415

Affected Software

Vendor	Product	Versions	Update
Linux	Linux Kernel	>= 6.6.120, < 6.6.136	—
Linux	Linux Kernel	>= 6.7, < 6.12.83	—
Linux	Linux Kernel	>= 6.13, < 6.18.24	—
Linux	Linux Kernel	>= 6.19, < 6.19.14	—
Linux	Linux Kernel	7.0	Rc1

References

Timeline

Published: May 6, 2026
Last Modified: Jun 17, 2026
Status: Analyzed

Frequently Asked Questions

What is CVE-2026-43120?

In the Linux kernel, the following vulnerability has been resolved: RDMA/irdma: Fix double free related to rereg_user_mr If IB_MR_REREG_TRANS is set during rereg_user_mr, the umem will be released and a new one will be allocated in irdma_rereg_mr_trans. If any step of irdma_rereg_mr_trans fails after the new umem is allocated, it releases the umem, but does not set iwmr->region to NULL. The problem is that this failure is propagated to the user, who will then call ibv_dereg_mr (as they should). Then, the dereg_mr path will see a non-NULL umem and attempt to call ib_umem_release again. Fix this by setting iwmr->region to NULL after ib_umem_release. Fixed: 5ac388db27c4 ("RDMA/irdma: Add support to re-register a memory region")

How severe is CVE-2026-43120?

CVE-2026-43120 has a CVSS score of 7.8/10 (HIGH severity). The EPSS model estimates a 0.12% probability of exploitation in the next 30 days.

How do I fix CVE-2026-43120?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.