Linux Kernel up to 6.16.0 ipv6 rt6_nlmsg_size infinite loop

Summaryinfo

A vulnerability was found in Linux Kernel up to 6.1.147/6.6.101/6.12.41/6.15.9/6.16.0. It has been rated as critical. This issue affects the function rt6_nlmsg_size of the component ipv6. The manipulation leads to infinite loop. This vulnerability is documented as CVE-2025-38588. There is not any exploit available. Upgrading the affected component is advised.

Detailsinfo

A vulnerability was found in Linux Kernel up to 6.1.147/6.6.101/6.12.41/6.15.9/6.16.0 and classified as critical. This issue affects the function rt6_nlmsg_size of the component ipv6. The manipulation with an unknown input leads to a infinite loop vulnerability. Using CWE to declare the problem leads to CWE-835. The product contains an iteration or loop with an exit condition that cannot be reached, i.e., an infinite loop. Impacted is availability. The summary by CVE is:

In the Linux kernel, the following vulnerability has been resolved: ipv6: prevent infinite loop in rt6_nlmsg_size() While testing prior patch, I was able to trigger an infinite loop in rt6_nlmsg_size() in the following place: list_for_each_entry_rcu(sibling, &f6i->fib6_siblings, fib6_siblings) { rt6_nh_nlmsg_size(sibling->fib6_nh, &nexthop_len); } This is because fib6_del_route() and fib6_add_rt2node() uses list_del_rcu(), which can confuse rcu readers, because they might no longer see the head of the list. Restart the loop if f6i->fib6_nsiblings is zero.

The advisory is shared at git.kernel.org. The identification of this vulnerability is CVE-2025-38588 since 04/16/2025. Technical details are known, but no exploit is available.

The vulnerability scanner Nessus provides a plugin with the ID 260111 (Linux Distros Unpatched Vulnerability : CVE-2025-38588), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 6.1.148, 6.6.102, 6.12.42, 6.15.10, 6.16.1 or 6.17-rc1 eliminates this vulnerability. Applying the patch 6d345136c9b875f065d226908a29c25cdf9343f8/e1b7932af47f92432be8303d2439d1bf77b0be23/cd8d8bbd9ced4cc5d06d858f67d4aa87745e8f38/3c13db3e47e170bab19e574404e7b6be45ea873d/46aeb66e9e54ed0d56c18615e1c3dbd502b327ab/54e6fe9dd3b0e7c481c2228782c9494d653546da 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.

The vulnerability is also documented in the databases at Tenable (260111), EUVD (EUVD-2025-27917) and CERT Bund (WID-SEC-2025-1869). If you want to get the best quality for vulnerability data then you always have to consider VulDB.

Affected

• Debian Linux
• Amazon Linux 2
• Red Hat Enterprise Linux
• Ubuntu Linux
• SUSE Linux
• Oracle Linux
• SUSE openSUSE
• RESF Rocky Linux
• Dell Avamar
• Open Source Linux Kernel
• Dell NetWorker
• Dell Secure Connect Gateway
• IBM QRadar SIEM

Productinfo

Type

• Operating System

Vendor

• Linux

Name

• Kernel

Version

• 6.0
• 6.1
• 6.1.147
• 6.2
• 6.3
• 6.4
• 6.5
• 6.6
• 6.6.101
• 6.7
• 6.8
• 6.9
• 6.10
• 6.11
• 6.12
• 6.12.0
• 6.12.1
• 6.12.2
• 6.12.3
• 6.12.4
• 6.12.5
• 6.12.6
• 6.12.7
• 6.12.8
• 6.12.9
• 6.12.10
• 6.12.11
• 6.12.12
• 6.12.13
• 6.12.14
• 6.12.15
• 6.12.16
• 6.12.17
• 6.12.18
• 6.12.19
• 6.12.20
• 6.12.21
• 6.12.22
• 6.12.23
• 6.12.24
• 6.12.25
• 6.12.26
• 6.12.27
• 6.12.28
• 6.12.29
• 6.12.30
• 6.12.31
• 6.12.32
• 6.12.33
• 6.12.34
• 6.12.35
• 6.12.36
• 6.12.37
• 6.12.38
• 6.12.39
• 6.12.40
• 6.12.41
• 6.13
• 6.14
• 6.15
• 6.15.0
• 6.15.1
• 6.15.2
• 6.15.3
• 6.15.4
• 6.15.5
• 6.15.6
• 6.15.7
• 6.15.8
• 6.15.9
• 6.16.0

License

• open-source

Website

• Vendor: https://www.kernel.org/

CPE 2.3info

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CPE 2.2info

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CVSSv4info

CVSSv3info

CVSSv2info

Exploitinginfo

Threat Intelligenceinfo

Countermeasuresinfo

Timelineinfo

Sourcesinfo

Entryinfo

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