CVE-2026-45852 RDMA/rxe: Fix double free in rxe_srq_from_init
A double free vulnerability in the Linux kernel's RDMA/rxe driver allows local attackers to potentially execute arbitrary code or escalate privileges.
- 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-2026-45852?
CVE-2026-45852 is a high-severity use after free vulnerability in Linux kernel, published on 27 May 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/rxe: Fix double free in rxe_srq_from_init
In rxe_srq_from_init(), the queue pointer 'q' is assigned to 'srq->rq.queue' before copying the SRQ number to user space. If copy_to_user() fails, the function calls rxe_queue_cleanup() to free the queue, but leaves the now-invalid pointer in 'srq->rq.queue'.
The caller of rxe_srq_from_init() (rxe_create_srq) eventually calls rxe_srq_cleanup() upon receiving the error, which triggers a second rxe_queue_cleanup() on the same memory, leading to a double free.
The call trace looks like this: kmem_cache_free+0x.../0x... rxe_queue_cleanup+0x1a/0x30 [rdma_rxe] rxe_srq_cleanup+0x42/0x60 [rdma_rxe] rxe_elem_release+0x31/0x70 [rdma_rxe] rxe_create_srq+0x12b/0x1a0 [rdma_rxe] ib_create_srq_user+0x9a/0x150 [ib_core]
Fix this by moving 'srq->rq.queue = q' after copy_to_user.
Which versions are affected by CVE-2026-45852?
It affects 1 product.
Products include Linux kernel.
How do I fix CVE-2026-45852?
Apply the vendor's patch.
Upgrade to the fixed version. These bugs are found with fuzzing and sanitisers and avoided by memory-safe languages. More about Use after free.
Is CVE-2026-45852 being exploited?
There is no known exploitation of CVE-2026-45852 in the wild and no public exploit code.
Other vulnerabilities in Linux kernel
Sources
Also known as BELL-CVE-2026-45852, DEBIAN-CVE-2026-45852, GHSA-m5rc-6p5x-73gp, ROOT-OS-DEBIAN-11-CVE-2026-45852, ROOT-OS-UBUNTU-2204-CVE-2026-45852, ROOT-OS-UBUNTU-2404-CVE-2026-45852 and 1 more.