CVE-2026-52908 RDMA: During rereg_mr ensure that REREG_ACCESS is compatible
A flaw in the Linux kernel RDMA subsystem allows improper memory access permissions, potentially enabling privilege escalation.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-52908?
CVE-2026-52908 is a high-severity vulnerability in Linux kernel, published on 19 Jun 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
In the Linux kernel, the following vulnerability has been resolved:
RDMA: During rereg_mr ensure that REREG_ACCESS is compatible
If IB_MR_REREG_ACCESS changes from RO to RW then the umem has to be re-evaluated to ensure it is properly pinned as RW. Since the umem is hidden inside each driver's mr struct add a ib_umem_check_rereg() function that each driver has to call before processing IB_MR_REREG_ACCESS.
mlx4 has to retain its duplicate ib_access_writable check because it implements IB_MR_REREG_ACCESS | IB_MR_REREG_TRANS by changing both items in place sequentially while the MR is live, so it will continue to not support this combination.
Weakness: CWE-285
Which versions are affected by CVE-2026-52908?
It affects 1 product.
Products include Linux kernel.
How do I fix CVE-2026-52908?
Apply the vendor's patch.
Is CVE-2026-52908 being exploited?
There is no known exploitation of CVE-2026-52908 in the wild and no public exploit code.
Other vulnerabilities in Linux kernel
Sources
Also known as BELL-CVE-2026-52908, DEBIAN-CVE-2026-52908, GHSA-2m6m-r8c9-84hh, ROOT-OS-UBUNTU-2404-CVE-2026-52908, UBUNTU-CVE-2026-52908.