cbcvebase.
CVE-2021-47010
published 2024-02-28

CVE-2021-47010: In the Linux kernel, the following vulnerability has been resolved: net: Only allow init netns to set default tcp cong to a restricted algo…

PriorityP338high7.8CVSS 3.1
AVLACLPRLUINSUCHIHAH
EPSS
0.26%
17.4th percentile
In the Linux kernel, the following vulnerability has been resolved: net: Only allow init netns to set default tcp cong to a restricted algo tcp_set_default_congestion_control() is netns-safe in that it writes to &net->ipv4.tcp_congestion_control, but it also sets ca->flags |= TCP_CONG_NON_RESTRICTED which is not namespaced. This has the unintended side-effect of changing the global net.ipv4.tcp_allowed_congestion_control sysctl, despite the fact that it is read-only: 97684f0970f6 ("net: Make tcp_allowed_congestion_control readonly in non-init netns") Resolve this netns "leak" by only allowing the init netns to set the default algorithm to one that is restricted. This restriction could be removed if tcp_allowed_congestion_control were namespace-ified in the future. This bug was uncovered with https://github.com/JonathonReinhart/linux-netns-sysctl-verify

Affected

17 ranges
VendorProductVersion rangeFixed in
debianlinux< linux 5.10.38-1 (bookworm)linux 5.10.38-1 (bookworm)
linuxlinux
linuxlinux>= 6670e152447732ba90626f36dfc015a13fbf150e < 992de06308d9a9584d59b96d294ac676f924e437992de06308d9a9584d59b96d294ac676f924e437
linuxlinux>= 6670e152447732ba90626f36dfc015a13fbf150e < 9884f745108f7d25b189bbcd6754e284fb29ab689884f745108f7d25b189bbcd6754e284fb29ab68
linuxlinux>= 6670e152447732ba90626f36dfc015a13fbf150e < 6c1ea8bee75df8fe2184a50fcd0f70bf82986f426c1ea8bee75df8fe2184a50fcd0f70bf82986f42
linuxlinux>= 6670e152447732ba90626f36dfc015a13fbf150e < efe1532a6e1a8e3c343d04fff510f0ed80328f9cefe1532a6e1a8e3c343d04fff510f0ed80328f9c
linuxlinux>= 6670e152447732ba90626f36dfc015a13fbf150e < e7d7bedd507bb732e600403b7a96f9fe48d0ca31e7d7bedd507bb732e600403b7a96f9fe48d0ca31
linuxlinux>= 6670e152447732ba90626f36dfc015a13fbf150e < 8d432592f30fcc34ef5a10aac4887b48978844938d432592f30fcc34ef5a10aac4887b4897884493
linuxlinux_kernel>= 0 < 5.10.38-15.10.38-1
linuxlinux_kernel>= 0 < 5.10.38-15.10.38-1
linuxlinux_kernel>= 0 < 5.10.38-15.10.38-1
linuxlinux_kernel>= 0 < 5.10.38-15.10.38-1
linuxlinux_kernel>= 4.15 < 4.19.1914.19.191
linuxlinux_kernel>= 4.20 < 5.4.1195.4.119
linuxlinux_kernel>= 5.11 < 5.11.215.11.21
linuxlinux_kernel>= 5.12 < 5.12.45.12.4
linuxlinux_kernel>= 5.5 < 5.10.375.10.37

CVSS provenance

nvdv3.17.8HIGHCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
osv7.8HIGH
vendor_debian7.8HIGH
vendor_redhat7.8HIGH
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