{"cve":"CVE-2021-38209","nvd":{"published":"2021-08-08T20:15:07.423","modified":"2026-06-17T04:01:46.067","status":"Modified","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.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N","score":3.3},"cwes":["CWE-203"],"references":["https://cdn.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.12.2","https://github.com/torvalds/linux/commit/2671fa4dc0109d3fb581bc3078fdf17b5d9080f6","https://cdn.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.12.2","https://github.com/torvalds/linux/commit/2671fa4dc0109d3fb581bc3078fdf17b5d9080f6"],"products":["linux:linux_kernel"],"source":"nvd","synced_at":"2026-10-19T21:21:13.713336758+00:00"},"epss":{"cve":"CVE-2021-38209","score":0.00283,"percentile":0.20907,"date":"2026-11-01"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}