7.8

CVE-2021-46966: linux Use After Free

CVSS: 7.8v3.1HighAnalyzed
AliasesUBUNTU-CVE-2021-46966DEBIAN-CVE-2021-46966
Published 27-02-2024Last modified 23-05-2026
Open JSON

Vulnerability summary

CVE-2021-46966 is a high (CVSS 7.8) Use After Free vulnerability in linux. EPSS estimates a 0.23% chance of exploitation in the next 30 days, higher than 12.8% of scored vulnerabilities.

Overall risk
31/100
0100
Medium · default modelHow is this calculated?
CVSS score
7.8/10
010
High · v3.1 (NVD)
EPSS score
0.23%
0%100%
Low · 0.00 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded

Advisory lineage

Upstream 0 · Downstream 7 · Related 7
SUSE-SU-2024:0856-1SUSE-SU-2024:0857-1SUSE-SU-2024:0926-1SUSE-SU-2024:1643-1SUSE-SU-2024:1646-1SUSE-SU-2024:1870-1

Timeline

  1. 27-02-2024
    PublishedVulnerability first disclosed.
  2. 23-05-2026
    Last modifiedVulnerability information updated.

Description

In the Linux kernel, the following vulnerability has been resolved: ACPI: custom_method: fix potential use-after-free issue In cm_write(), buf is always freed when reaching the end of the function. If the requested count is less than table.length, the allocated buffer will be freed but subsequent calls to cm_write() will still try to access it. Remove the unconditional kfree(buf) at the end of the function and set the buf to NULL in the -EINVAL error path to match the rest of function.

CVSS metrics

3 scores · 3 sources · 1 version

EPSS trend

Probability

0.23%

Chance of exploitation in the next 30 days

Percentile

13%

Versus all other CVEs

30-day change

0.00 pp

From 0.23% on 19-09-2026

19-09-202619-10-2026
EPSS score
0.23%

Known exploited

Compare KEV catalogs

Not in any of the 3 tracked catalogs.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

Ubuntu86 products
  • linux< 4.4.0-253.287 | < 4.15.0-151.157 | < 5.4.0-77.86
  • linux-allwinner-5.19All versions (No fix recorded)
  • linux-aws< 4.4.0-1130.136 | < 4.4.0-1168.183 | < 4.15.0-1109.116 | < 5.4.0-1051.53
  • linux-aws-5.0All versions (No fix recorded)
  • linux-aws-5.11All versions (No fix recorded)
Linux2 products
  • linux≥ 4bda2b79a9d04c8ba31681c66e95877dbb433416, < 1d53ca5d131074c925ce38361fb0376d3bf7e394 | ≥ 5c12dadcbef8cd55ef1f5dac799bfcbb7ea7db1d, < 8b04d57f30caf76649d0567551589af9a66ca9be | ≥ 35b88a10535edcf62d3e6b7893a8cd506ff98a24, < 90575d1d9311b753cf1718f4ce9061ddda7dfd23 | ≥ e4467fb6ef547aa352dc03397f9474ec84eced5b, < a5b26a2e362f572d87e9fd35435680e557052a17 | ≥ 03d1571d9513369c17e6848476763ebbd10ec2cb, < 72814a94c38a33239793f7622cec6ace1e540c4b | ≥ 03d1571d9513369c17e6848476763ebbd10ec2cb, < 62dc2440ebb552aa0d7f635e1697e077d9d21203 | ≥ 03d1571d9513369c17e6848476763ebbd10ec2cb, < f16737caf41fc06cfe6e49048becb09657074d4b | ≥ 03d1571d9513369c17e6848476763ebbd10ec2cb, < b7a5baaae212a686ceb812c32fceed79c03c0234 | ≥ 03d1571d9513369c17e6848476763ebbd10ec2cb, < e483bb9a991bdae29a0caa4b3a6d002c968f94aa | 70424999fbf1f160ade111cb9baab51776e0f9c2 | 06cd4a06eb596a888239fb8ceb6ea15677cab396 | ≥ 4.4.195, < 4.4.269 | ≥ 4.9.195, < 4.9.269 | ≥ 4.14.147, < 4.14.233 | ≥ 4.19.77, < 4.19.191 | ≥ 5.2.19, < 5.3 | ≥ 5.3.4, < 5.4 | 5.4
  • linux_kernel≥ 4.4.195, < 4.4.269 | ≥ 4.9.195, < 4.9.269 | ≥ 4.14.147, < 4.14.233 | ≥ 4.19.77, < 4.19.191 | ≥ 5.4, < 5.4.118 | ≥ 5.5, < 5.10.36 | ≥ 5.11, < 5.11.20 | ≥ 5.12, < 5.12.3
Debian1 product
  • linux< 5.10.38-1

3 vendors · 89 products

References

14 links
Show all 14 references