8.8

CVE-2021-34866: linux kernel

Modified
AliasesUBUNTU-CVE-2021-34866DEBIAN-CVE-2021-34866
Published 25-01-2022Last modified 08-10-2026

Vulnerability summary

CVE-2021-34866 is a high (CVSS 8.8) vulnerability in linux kernel. EPSS estimates a 0.97% chance of exploitation in the next 30 days, higher than 62% of scored vulnerabilities.

Priority
Routine

Not severe (CVSS 8.8, local access); no exploitation reported by the 5 checked sources

Source freshness unavailable

How is this decided?
CVSS score
8.8/10
010
High · v3.0 (CVE.org)
EPSS score
0.97%
0%100%
Low · 0.00 pp in 30 days
KEVNot listedNot listed by any tracked catalog.
RansomwareNot flaggedNo ransomware use recorded.
Public exploits0No public exploits recorded

Advisory lineage

Upstream 0 · Downstream 9 · Related 8
OPENSUSE-SU-2021:3641-1OPENSUSE-SU-2021:3675-1RHSA-2024:0724SUSE-SU-2021:3641-1SUSE-SU-2021:3642-1SUSE-SU-2021:3675-1

Timeline

  1. 25-01-2022
    PublishedVulnerability first disclosed.
  2. 08-10-2026
    Last modifiedVulnerability information updated.

Description

This vulnerability allows local attackers to escalate privileges on affected installations of Linux Kernel 5.14-rc3. An attacker must first obtain the ability to execute low-privileged code on the target system in order to exploit this vulnerability. The specific flaw exists within the handling of eBPF programs. The issue results from the lack of proper validation of user-supplied eBPF programs, which can result in a type confusion condition. An attacker can leverage this vulnerability to escalate privileges and execute arbitrary code in the context of the kernel. Was ZDI-CAN-14689.

CVSS metrics

7 scores · 4 sources · 3 versions

EPSS trend

Probability

0.97%

Chance of exploitation in the next 30 days

Percentile

62%

Versus all other CVEs

30-day change

No change 0.00 pp

From 0.97% on 04-10-2026

04-10-202603-11-2026

Known exploited

Compare KEV catalogs
CISA KEV

Not in the CISA KEV catalog.

ENISA CNW

Not in the ENISA CNW catalog.

CIRCL

Not in the CIRCL catalog.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

Version check

Known conditions: local access, low-privilege account, no user interaction (CVSS vector). Other conditions: not stated in public data.

Ubuntu31 products
  • linux-aws-5.0All versions (No fix recorded)
  • linux-aws-5.11< 5.11.0-1020.21~20.04.2
  • linux-aws-5.3All versions (No fix recorded)
  • linux-aws-5.8All versions (No fix recorded)
  • linux-azureAll versions (No fix recorded)
Netapp8 products
Linux2 products
Debian1 product
  • linux< 5.14.6-1

4 vendors · 42 products

References

6 links