Review reviewHigh

CVE-2021-47388

Linux Linux, linux kernel

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...

CVSS
7.8
EPSS
0.34%
26.4% percentile
CISA KEV
Not listed
Published
2024.05.22
PRIORITY ASSESSMENT

Review review

The CVSS severity warrants an early asset and exposure review.

Known exploitationNot established by KEV
Exploit probability0.34%
Technical severityCVSS 7.8

Vulnerability overview

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...

Affected product and versions

Product
Linux Linux, linux kernel
Affected versions
>= 608b0a2ae928a74a2f89e02227339dd79cdb63cf < 447d001b875d0e7f211c4ba004916028da994258, >= d0f613fe6de344dc17ba04a88921a2094c13d3fa < 31de381aef0ab1b342f62485118dc8a19363dc78, >= a9b57952fed41556c950a92123086724eaf11919 < f556e1d6fb9f2923a9a36f3df638c7d79ba09dbb, >= 0f716b48ed25503e6961f4b5b40ece36f7e4ed26 < 3d5d629c99c468458022e9b381789de3595bf4dd, >= c8b3a6150dc8ac78d5fdd5fbdfc4806249ef8b2c < 50149e0866a82cef33e680ee68dc380a5bc75d32, >= e64ea0597050157f926ac2ba9b478a44ee5be945 < 57de2dcb18742dc2860861c9f496da7d42b67da0, >= bf30ca922a0c0176007e074b0acc77ed345e9990 < 27d3eb5616ee2c0a3b30c3fa34813368ed1f3dc9, >= bf30ca922a0c0176007e074b0acc77ed345e9990 < 94513069eb549737bcfc3d988d6ed4da948a2de8, >= 1f0bf30c01d3f4de7d6c5e27b102a808c5646676, >= 4.4.271 < 4.4.286, >= 4.9.271 < 4.9.285, >= 4.14.235 < 4.14.249, >= 4.19.193 < 4.19.209, >= 5.4.124 < 5.4.151, >= 5.10.42 < 5.10.71, >= 5.12.9 < 5.13, >= 5.13, >= 5.12.9 < 5.14.10, 5.15
Fixed versions
4.4.286, 4.9.285, 4.14.249, 4.19.209, 5.4.151, 5.10.71, 5.14.10

Recommended response sequence

Confirm exposure before applying a vendor-supported change.

Full remediation guide
  1. 1
    Identify

    Confirm that Linux Linux, linux kernel and an affected version are present.

  2. 2
    Prioritize

    Combine exploitation signals with asset exposure and business criticality.

  3. 3
    Remediate

    Follow the vendor advisory or supported update path and preserve rollback options.

  4. 4
    Verify

    Recheck the version, service health, access paths, and relevant logs.

Technical data

CVSS vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
CWE
CWE-416
CVE-2021-47388 — Linux Linux, linux kernel | SECUFOCUS NOW