CVE-2021-38209
published 2021-08-08CVE-2021-38209: 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…
PriorityP411low3.3CVSS 3.1
AVLACLPRLUINSUCLINAN
EPSS
0.28%
20.7th percentile
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.
Affected
8 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| debian | linux | < linux 5.10.38-1 (bookworm) | linux 5.10.38-1 (bookworm) |
| linux | linux_kernel | < 5.12.2 | 5.12.2 |
| linux | linux_kernel | >= 0 < 5.10.38-1 | 5.10.38-1 |
| linux | linux_kernel | >= 0 < 5.10.38-1 | 5.10.38-1 |
| linux | linux_kernel | >= 0 < 5.10.38-1 | 5.10.38-1 |
| linux | linux_kernel | >= 0 < 5.10.38-1 | 5.10.38-1 |
| msrc | cbl2_kernel_5.10.78.1-1_on_cbl_mariner_2.0 | — | — |
| msrc | cm1_kernel_5.10.60.1-1_on_cbl_mariner_1.0 | — | — |
CVSS provenance
nvdv3.13.3LOWCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N
nvdv2.02.1LOWAV:L/AC:L/Au:N/C:P/I:N/A:N
osv3.3LOW
vendor_debian3.3LOW
vendor_msrc3.3LOW
vendor_redhat3.3LOW
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Microsoft
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 rel
vendor_msrc·2021-08-10·CVSS 3.3
CVE-2021-38209 [LOW] CWE-203 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 rel
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.
FAQ: Is Azure Linux the only Microsoft product that includes this open-source library and is therefore potentially affected by this vulnerability?
One of the main benefits to our customers who choose to use the Azure Linux distro is the commitment to keep it up to date with the most recent and most secure versions of the open source libraries with which the distro is composed. Microsoft is committed to transparency in this work which is why we began publishing CSAF/VEX in October 2025. See this blog post fo
Red Hat
kernel: net/netfilter/nf_conntrack_standalone.c allows observation of changes in any net namespace because these changes are leaked into all other net namespaces
vendor_redhat·2021-04-12·CVSS 3.3
CVE-2021-38209 [LOW] CWE-200 kernel: net/netfilter/nf_conntrack_standalone.c allows observation of changes in any net namespace because these changes are leaked into all other net namespaces
kernel: net/netfilter/nf_conntrack_standalone.c allows observation of changes in any net namespace because these changes are leaked into all other net namespaces
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.
A flaw was found in the Linux kernel. Observation of changes in any net namespace is possible due to these changes being leaked into all other net namespaces. The highest threat from this vulnerability is to data confidentiality.
Package: kernel (Red Hat Enterprise Linux 5) - Out of support scope
Package: kernel (Red Hat Enterprise Linux 6) -
Debian
CVE-2021-38209: linux - net/netfilter/nf_conntrack_standalone.c in the Linux kernel before 5.12.2 allows...
vendor_debian·2021·CVSS 3.3
CVE-2021-38209 [LOW] CVE-2021-38209: linux - net/netfilter/nf_conntrack_standalone.c in the Linux kernel before 5.12.2 allows...
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.
Scope: local
bookworm: resolved (fixed in 5.10.38-1)
bullseye: resolved (fixed in 5.10.38-1)
forky: resolved (fixed in 5.10.38-1)
sid: resolved (fixed in 5.10.38-1)
trixie: resolved (fixed in 5.10.38-1)
GHSA
GHSA-vj8v-34wr-vjm9: net/netfilter/nf_conntrack_standalone
ghsa_unreviewed·2022-05-24
CVE-2021-38209 [LOW] CWE-203 GHSA-vj8v-34wr-vjm9: net/netfilter/nf_conntrack_standalone
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.
OSV
CVE-2021-38209: net/netfilter/nf_conntrack_standalone
osv·2021-08-08·CVSS 3.3
CVE-2021-38209 [LOW] CVE-2021-38209: net/netfilter/nf_conntrack_standalone
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.
No detection rules found.
No public exploits indexed.
No writeups or analysis indexed.
2021-08-08
Published