CVE-2026-64033 RDMA/rtrs: Fix use-after-free in path file creation cleanup

What is CVE-2026-64033?

CVE-2026-64033 is a critical use after free vulnerability in Linux kernel, published on 19 Jul 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official description

In the Linux kernel, the following vulnerability has been resolved:

RDMA/rtrs: Fix use-after-free in path file creation cleanup

In the error path of rtrs_srv_create_path_files(), the sysfs root folders may already have been created and srv_path->kobj may already have been initialized. If a later step fails, the cleanup currently calls kobject_put(&srv_path->kobj) before rtrs_srv_destroy_once_sysfs_root_folders(srv_path).

kobject_put() may drop the last reference to srv_path->kobj and invoke the release callback, rtrs_srv_release(), which frees srv_path. The following call to rtrs_srv_destroy_once_sysfs_root_folders(srv_path) then dereferences srv_path internally to access srv_path->srv, resulting in a use-after-free.

This failure path is reached before rtrs_srv_create_path_files() returns success, so the successful-path lifetime handling is not involved.

Fix this by destroying the sysfs root folders before calling kobject_put(&srv_path->kobj), so srv_path is still valid while the helper accesses it.

This issue was found by a static analysis tool I am developing.

Weakness: CWE-416

Which versions are affected by CVE-2026-64033?

It affects 1 product.

Products include Linux kernel.

How do I fix CVE-2026-64033?

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-2026-64033 being exploited?

There is no known exploitation of CVE-2026-64033 in the wild and no public exploit code.

Other vulnerabilities in Linux kernel

• CVE-2026-53266 Linux Kernel Out-of-Bounds Write Exploited High 8.8
• CVE-2013-6282 Linux Kernel Improper Input Validation Exploited High 8.8
• CVE-2022-0185 Linux Kernel Heap-Based Buffer Overflow Exploited High 8.4
• CVE-2013-2094 Linux Kernel Privilege Escalation Exploited High 8.4
• CVE-2026-53362 Linux Kernel Unspecified Exploited High 7.8

All Linux kernel vulnerabilities

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as BELL-CVE-2026-64033, DEBIAN-CVE-2026-64033, GHSA-2qpc-f6fh-fxg4, UBUNTU-CVE-2026-64033.