SB2021080816 - Observable discrepancy in Linux kernel



SB2021080816 - Observable discrepancy in Linux kernel

Published: August 8, 2021

Security Bulletin ID SB2021080816
CSH Severity
Low
Patch available
YES
Number of vulnerabilities 1
Exploitation vector Local access
Highest impact Information disclosure

Breakdown by Severity

Low 100%
  • Low
  • Medium
  • High
  • Critical

Description

This security bulletin contains information about 1 vulnerability.


1) Observable discrepancy (CVE-ID: CVE-2021-38209)

CWE-ID: CWE-203 - Observable discrepancy

CVSSv4: 4.8 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N]


The vulnerability allows a local user to gain access to sensitive information.

net/netfilter/nf_conntrack_standalone.c in the Linux kernel before 5.12.2 allows observation of changes in any net namespace because these changes are leaked into all other net namespaces. This is related to the NF_SYSCTL_CT_MAX, NF_SYSCTL_CT_EXPECT_MAX, and NF_SYSCTL_CT_BUCKETS sysctls.


Remediation

Install update from vendor's website.