Linux Kernel up to 5.12.3 tcp_set_default_congestion_control information disclosure

Summaryinfo

A vulnerability classified as problematic has been found in Linux Kernel up to 4.19.190/5.4.118/5.10.36/5.11.20/5.12.3. Impacted is the function tcp_set_default_congestion_control. Performing a manipulation results in information disclosure. This vulnerability is identified as CVE-2021-47010. There is not any exploit available. It is recommended to upgrade the affected component.

Detailsinfo

A vulnerability classified as problematic has been found in Linux Kernel up to 4.19.190/5.4.118/5.10.36/5.11.20/5.12.3 (Operating System). This affects the function tcp_set_default_congestion_control. The manipulation with an unknown input leads to a information disclosure vulnerability. CWE is classifying the issue as CWE-200. The product exposes sensitive information to an actor that is not explicitly authorized to have access to that information. This is going to have an impact on confidentiality. The summary by CVE is:

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

The weakness was released 02/28/2024. It is possible to read the advisory at git.kernel.org. This vulnerability is uniquely identified as CVE-2021-47010 since 02/27/2024. Technical details of the vulnerability are known, but there is no available exploit. The attack technique deployed by this issue is T1592 according to MITRE ATT&CK.

Upgrading to version 4.19.191, 5.4.119, 5.10.37, 5.11.21, 5.12.4 or 5.13 eliminates this vulnerability. Applying the patch 992de06308d9/9884f745108f/6c1ea8bee75d/efe1532a6e1a/e7d7bedd507b/8d432592f30f is able to eliminate this problem. The bugfix is ready for download at git.kernel.org. The best possible mitigation is suggested to be upgrading to the latest version.

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Productinfo

Type

• Operating System

Vendor

• Linux

Name

• Kernel

Version

• 4.19.190
• 5.4.118
• 5.10.0
• 5.10.1
• 5.10.2
• 5.10.3
• 5.10.4
• 5.10.5
• 5.10.6
• 5.10.7
• 5.10.8
• 5.10.9
• 5.10.10
• 5.10.11
• 5.10.12
• 5.10.13
• 5.10.14
• 5.10.15
• 5.10.16
• 5.10.17
• 5.10.18
• 5.10.19
• 5.10.20
• 5.10.21
• 5.10.22
• 5.10.23
• 5.10.24
• 5.10.25
• 5.10.26
• 5.10.27
• 5.10.28
• 5.10.29
• 5.10.30
• 5.10.31
• 5.10.32
• 5.10.33
• 5.10.34
• 5.10.35
• 5.10.36
• 5.11.0
• 5.11.1
• 5.11.2
• 5.11.3
• 5.11.4
• 5.11.5
• 5.11.6
• 5.11.7
• 5.11.8
• 5.11.9
• 5.11.10
• 5.11.11
• 5.11.12
• 5.11.13
• 5.11.14
• 5.11.15
• 5.11.16
• 5.11.17
• 5.11.18
• 5.11.19
• 5.11.20
• 5.12.0
• 5.12.1
• 5.12.2
• 5.12.3

License

• open-source

Website

• Vendor: https://www.kernel.org/

CPE 2.3info

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CPE 2.2info

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