CVE-2021-38209 Information disclosure in n/a

What is CVE-2021-38209?

CVE-2021-38209 is a low-severity vulnerability in Linux kernel, published on 8 Aug 2021. It can only be exploited from the same machine or local network, with no action from the victim.

Official description

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.

Weakness: CWE-203

Which versions are affected by CVE-2021-38209?

It affects 1 product.

Products include Linux kernel.

How do I fix CVE-2021-38209?

Upgrade to a fixed version.

Is CVE-2021-38209 being exploited?

There is no known exploitation of CVE-2021-38209 in the wild and no public exploit code.

Other vulnerabilities in Linux kernel

• CVE-2026-53266 Linux Kernel Out-of-Bounds Write Exploited High 8.8
• CVE-2013-6282 Linux Kernel Improper Input Validation Exploited High 8.8
• CVE-2022-0185 Linux Kernel Heap-Based Buffer Overflow Exploited High 8.4
• CVE-2013-2094 Linux Kernel Privilege Escalation Exploited High 8.4
• CVE-2026-53362 Linux Kernel Unspecified Exploited High 7.8

All Linux kernel vulnerabilities

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as AZL-6593, DEBIAN-CVE-2021-38209, GHSA-vj8v-34wr-vjm9, UBUNTU-CVE-2021-38209.