CVE-2021-47388: mac80211: fix use-after-free in CCMP/GCMP RX
Vulnerability summary
CVE-2021-47388 is a high (CVSS 8.8) Use After Free vulnerability in linux. EPSS estimates a 0.34% chance of exploitation in the next 30 days, higher than 27.7% of scored vulnerabilities.
Not severe (CVSS 8.8, adjacent network); no exploitation reported by the 5 checked sources
Source freshness unavailable
How is this decided?Advisory lineage
Upstream 0 · Downstream 11 · Related 11Timeline
- 21-05-2024PublishedVulnerability first disclosed.
- 05-08-2026Last modifiedVulnerability information updated.
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.
CVSS metrics
4 scores · 4 sources · 1 version- OSV · UbuntuEcosystem advisory · calculated8.8HighCVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
- OSV · DebianEcosystem advisory · calculated7.8HighCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:HDiffers
- NVDNIST7.8HighCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:HDiffers
EPSS trend
Probability
0.34%
Chance of exploitation in the next 30 days
Percentile
28%
Versus all other CVEs
30-day change
No change 0.00 pp
From 0.34% on 04-10-2026
Known exploited
Compare KEV catalogs
CISA KEVNot in the CISA KEV catalog.
ENISA CNWNot in the ENISA CNW catalog.
CIRCLNot in the CIRCL catalog.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root causeAffected systems
Known conditions: adjacent network, no authentication, no user interaction (CVSS vector). Other conditions: not stated in public data.
Ubuntu86 products
- linux< 4.15.0-163.171 | < 5.4.0-91.102
- linux-allwinner-5.19All versions (No fix recorded)
- linux-aws< 4.15.0-1116.123 | < 5.4.0-1060.63
- linux-aws-5.0All versions (No fix recorded)
- linux-aws-5.11All versions (No fix recorded)
Linux2 products
- linux≥ 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
- linux_kernel≥ 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, < 5.14.10 | 5.15:rc1 | 5.15:rc2 | 5.15:rc3
Debian1 product
- linux< 5.14.12-1
3 vendors · 89 products
