CVE-2026-98210 mmc: mxcmmc: cancel data work and watchdog on remove
A use-after-free vulnerability in the Linux kernel mxcmmc driver allows local attackers to cause a denial of service or potentially execute code via race conditions during device removal.
- 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-2026-98210?
CVE-2026-98210 is an use after free vulnerability in Linux, published on 6 Oct 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:
mmc: mxcmmc: cancel data work and watchdog on remove
mxcmci_remove() frees the host through the devm tail, but neither it nor mmc_remove_host() drains the driver's own asynchronous state. host->watchdog, a 10 s timer armed on the DMA path in mxcmci_setup_data(), is deleted only by the DMA- and IRQ-complete paths, which the remove path does not explicitly drain; it can therefore fire after the host is freed and dereference it in mxcmci_watchdog(). host->datawork, armed from the IRQ handler on the PIO path, is not cancelled by the remove path either.
Free the devm-registered IRQ, then cancel datawork and delete the watchdog in mxcmci_remove(), before dma_release_channel(). Freeing the IRQ first keeps a trailing handler from re-arming datawork between the cancel and the host free. Both callbacks are non-self-rearming.
This issue was found by an in-house static analysis tool.
Which versions are affected by CVE-2026-98210?
How do I fix CVE-2026-98210?
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-2026-98210 being exploited?
There is no known exploitation of CVE-2026-98210 in the wild and no public exploit code.
Sources
Also known as AZL-106245, BELL-CVE-2026-98210, DEBIAN-CVE-2026-98210, GHSA-3899-r8v9-5w9h, UBUNTU-CVE-2026-98210.