CVE-2026-72149 dmaengine: tegra: Fix burst size calculation
A flaw in the Tegra GPC DMA driver causes system hangs during UART transfers with non-aligned lengths, requiring a kernel patch to resolve.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-72149?
CVE-2026-72149 is a high-severity denial of service vulnerability in Linux, published on 15 Aug 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:
dmaengine: tegra: Fix burst size calculation
Currently, the Tegra GPC DMA hardware requires the transfer length to be a multiple of the max burst size configured for the channel. When a client requests a transfer where the length is not evenly divisible by the configured max burst size, the DMA hangs with partial burst at the end.
Fix this by reducing the burst size to the largest power-of-2 value that evenly divides the transfer length. For example, a 40-byte transfer with a 16-byte max burst will now use an 8-byte burst (40 / 8 = 5 complete bursts) instead of causing a hang.
This issue was observed with the PL011 UART driver where TX DMA transfers of arbitrary lengths were stuck.
Which versions are affected by CVE-2026-72149?
How do I fix CVE-2026-72149?
Apply the vendor's patch.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2026-72149 being exploited?
There is no known exploitation of CVE-2026-72149 in the wild and no public exploit code.
Sources
Also known as BELL-CVE-2026-72149, DEBIAN-CVE-2026-72149, GHSA-jjfr-vvvg-vj2f, UBUNTU-CVE-2026-72149.