CVE-2025-40018

Description

In the Linux kernel, the following vulnerability has been resolved: ipvs: Defer ip_vs_ftp unregister during netns cleanup On the netns cleanup path, __ip_vs_ftp_exit() may unregister ip_vs_ftp before connections with valid cp->app pointers are flushed, leading to a use-after-free. Fix this by introducing a global `exiting_module` flag, set to true in ip_vs_ftp_exit() before unregistering the pernet subsystem. In __ip_vs_ftp_exit(), skip ip_vs_ftp unregister if called during netns cleanup (when exiting_module is false) and defer it to __ip_vs_cleanup_batch(), which unregisters all apps after all connections are flushed. If called during module exit, unregister ip_vs_ftp immediately.

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References

Other References

https://git.kernel.org/stable/c/134121bfd99a06d44ef5ba15a9beb075297c0821 https://git.kernel.org/stable/c/1d79471414d7b9424d699afff2aa79fff322f52d https://git.kernel.org/stable/c/421b1ae1574dfdda68b835c15ac4921ec0030182 https://git.kernel.org/stable/c/53717f8a4347b78eac6488072ad8e5adbaff38d9 https://git.kernel.org/stable/c/8a6ecab3847c213ce2855b0378e63ce839085de3 https://git.kernel.org/stable/c/8cbe2a21d85727b66d7c591fd5d83df0d8c4f757 https://git.kernel.org/stable/c/a343811ef138a265407167294275201621e9ebb2 https://git.kernel.org/stable/c/dc1a481359a72ee7e548f1f5da671282a7c13b8f

Frequently Asked Questions

What is CVE-2025-40018? +

In the Linux kernel, the following vulnerability has been resolved: ipvs: Defer ip_vs_ftp unregister during netns cleanup On the netns cleanup path, __ip_vs_ftp_exit() may unregister ip_vs_ftp before connections with valid cp->app pointers are flushed, leading to a use-after-free. Fix this by introducing a global `exiting_module` flag, set to true in ip_vs_ftp_exit() before unregistering the pernet subsystem. In __ip_vs_ftp_exit(), skip ip_vs_ftp unregister if called during netns cleanup (when exiting_module is false) and defer it to __ip_vs_cleanup_batch(), which unregisters all apps after all connections are flushed. If called during module exit, unregister ip_vs_ftp immediately.

How do I check if I'm vulnerable to CVE-2025-40018? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

CVE-2025-40018

Description

References

Other References

Frequently Asked Questions

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