CVE-2026-63797 rpmsg: char: Fix use-after-free on probe error path
A use-after-free in the Linux kernel rpmsg char driver allows attackers to potentially execute code or escalate privileges via a probe error path.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-63797?
CVE-2026-63797 is a high-severity use after free vulnerability in Linux kernel, published on 19 Jul 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:
rpmsg: char: Fix use-after-free on probe error path
rpmsg_chrdev_probe() stores the newly allocated eptdev in the default endpoint's priv pointer before calling rpmsg_chrdev_eptdev_add(). If rpmsg_chrdev_eptdev_add() then fails, its error path frees eptdev while the default endpoint may still dispatch callbacks with the stale priv pointer.
Avoid publishing eptdev through the default endpoint until rpmsg_chrdev_eptdev_add() succeeds. Messages received before the priv pointer is published should be ignored by rpmsg_ept_cb(). Flow-control updates can hit rpmsg_ept_flow_cb() in the same window, so make both callbacks return success when priv is NULL.
Weakness: CWE-416
Which versions are affected by CVE-2026-63797?
It affects 1 product.
Products include Linux kernel.
How do I fix CVE-2026-63797?
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-2026-63797 being exploited?
There is no known exploitation of CVE-2026-63797 in the wild and no public exploit code.
Other vulnerabilities in Linux kernel
Sources
Also known as BELL-CVE-2026-63797, DEBIAN-CVE-2026-63797, GHSA-86gp-v777-h747, ROOT-OS-DEBIAN-12-CVE-2026-63797, UBUNTU-CVE-2026-63797.