CVE-2021-47388

HIGH
Published May 21, 2024 Modified Dec 30, 2024 CWE-416

Description

In the Linux kernel, the following vulnerability has been resolved: mac80211: fix use-after-free in CCMP/GCMP RX When PN checking is done in mac80211, for fragmentation we need to copy the PN to the RX struct so we can later use it to do a comparison, since commit bf30ca922a0c ("mac80211: check defrag PN against current frame"). Unfortunately, in that commit I used the 'hdr' variable without it being necessarily valid, so use-after-free could occur if it was necessary to reallocate (parts of) the frame. Fix this by reloading the variable after the code that results in the reallocations, if any. This fixes https://bugzilla.kernel.org/show_bug.cgi?id=214401.

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CVSS v3.1 Score

7.8
HIGH
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Weakness Type (CWE)

CWE-416 Use After Free

Affected Products

Vendor Product
linux linux_kernel
linux linux_kernel
linux linux_kernel
linux linux_kernel
linux linux_kernel
linux linux_kernel
linux linux_kernel
linux linux_kernel
linux linux_kernel
linux linux_kernel

References

Advisories & Patches

https://git.kernel.org/stable/c/27d3eb5616ee2c0a3b30c3fa34813368ed1f3dc9 https://git.kernel.org/stable/c/31de381aef0ab1b342f62485118dc8a19363dc78 https://git.kernel.org/stable/c/3d5d629c99c468458022e9b381789de3595bf4dd https://git.kernel.org/stable/c/447d001b875d0e7f211c4ba004916028da994258 https://git.kernel.org/stable/c/50149e0866a82cef33e680ee68dc380a5bc75d32 https://git.kernel.org/stable/c/57de2dcb18742dc2860861c9f496da7d42b67da0 https://git.kernel.org/stable/c/94513069eb549737bcfc3d988d6ed4da948a2de8 https://git.kernel.org/stable/c/f556e1d6fb9f2923a9a36f3df638c7d79ba09dbb https://git.kernel.org/stable/c/27d3eb5616ee2c0a3b30c3fa34813368ed1f3dc9 https://git.kernel.org/stable/c/31de381aef0ab1b342f62485118dc8a19363dc78 https://git.kernel.org/stable/c/3d5d629c99c468458022e9b381789de3595bf4dd https://git.kernel.org/stable/c/447d001b875d0e7f211c4ba004916028da994258 https://git.kernel.org/stable/c/50149e0866a82cef33e680ee68dc380a5bc75d32 https://git.kernel.org/stable/c/57de2dcb18742dc2860861c9f496da7d42b67da0 https://git.kernel.org/stable/c/94513069eb549737bcfc3d988d6ed4da948a2de8 https://git.kernel.org/stable/c/f556e1d6fb9f2923a9a36f3df638c7d79ba09dbb

Frequently Asked Questions

What is CVE-2021-47388? +
In the Linux kernel, the following vulnerability has been resolved: mac80211: fix use-after-free in CCMP/GCMP RX When PN checking is done in mac80211, for fragmentation we need to copy the PN to the RX struct so we can later use it to do a comparison, since commit bf30ca922a0c ("mac80211: check defrag PN against current frame"). Unfortunately, in that commit I used the 'hdr' variable without it being necessarily valid, so use-after-free could occur if it was necessary to reallocate (parts of) the frame. Fix this by reloading the variable after the code that results in the reallocations, if any. This fixes https://bugzilla.kernel.org/show_bug.cgi?id=214401. It has a CVSS v3.1 base score of 7.8 (HIGH).
How severe is CVE-2021-47388? +
CVE-2021-47388 has a CVSS v3.1 score of 7.8 out of 10, rated HIGH. This is a high-severity vulnerability that should be prioritized for patching.
What products are affected by CVE-2021-47388? +
CVE-2021-47388 affects products from linux, specifically: linux_kernel. Check the affected products table above for specific version ranges.
How do I check if I'm vulnerable to CVE-2021-47388? +
You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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