CVE-2026-90077

Published Sep 17, 2026

Description

In the Linux kernel, the following vulnerability has been resolved: net: fix a resource leak in copy_net_ns() error handling path Currently, preinit_net() does two things: (1) call ns_common_init() which might fail (2) initialize resources which does not fail However, preinit_net() is returning early when (1) fails, and copy_net_ns() is jumping to the dec_ucounts: label. As a result, resources allocated by net_alloc() are leaking. We need to call key_remove_domain() and net_passive_dec() in order to release resources allocated by net_alloc(). We cannot simply jump to the put_userns: label when preinit_net() failed, for (2) is not yet done. But we can reorder (1) and (2), for there is no dependency between (1) and (2). Therefore, this patch decouples (1) from preinit_net() and changes preinit_net() back to a void function, and calls ns_common_init() after preinit_net() succeeded. Then, we can jump to immediately after ns_common_free() of the put_userns: label.

Is your site exposed to CVE-2026-90077?

Run a free security scan — no signup, results in seconds.

References

Frequently Asked Questions

What is CVE-2026-90077? +
In the Linux kernel, the following vulnerability has been resolved: net: fix a resource leak in copy_net_ns() error handling path Currently, preinit_net() does two things: (1) call ns_common_init() which might fail (2) initialize resources which does not fail However, preinit_net() is returning early when (1) fails, and copy_net_ns() is jumping to the dec_ucounts: label. As a result, resources allocated by net_alloc() are leaking. We need to call key_remove_domain() and net_passive_dec() in order to release resources allocated by net_alloc(). We cannot simply jump to the put_userns: label when preinit_net() failed, for (2) is not yet done. But we can reorder (1) and (2), for there is no dependency between (1) and (2). Therefore, this patch decouples (1) from preinit_net() and changes preinit_net() back to a void function, and calls ns_common_init() after preinit_net() succeeded. Then, we can jump to immediately after ns_common_free() of the put_userns: label.
How do I check if I'm vulnerable to CVE-2026-90077? +
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.

Don't wait for an exploit

Scan your website for vulnerabilities like CVE-2026-90077 — free, no signup required.