CVE-2021-47064 mt76: fix potential DMA mapping leak

What is CVE-2021-47064?

CVE-2021-47064 is a medium-severity memory corruption vulnerability in Linux kernel, published on 29 Feb 2024. 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:

mt76: fix potential DMA mapping leak

With buf uninitialized in mt76_dma_tx_queue_skb_raw, its field skip_unmap could potentially inherit a non-zero value from stack garbage. If this happens, it will cause DMA mappings for MCU command frames to not be unmapped after completion

Weakness: CWE-401

Which versions are affected by CVE-2021-47064?

It affects 1 product.

Products include Linux kernel.

How do I fix CVE-2021-47064?

Apply the vendor's patch.

Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.

Is CVE-2021-47064 being exploited?

There is no known exploitation of CVE-2021-47064 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 DEBIAN-CVE-2021-47064, GHSA-vv74-wh7g-52xw, UBUNTU-CVE-2021-47064.