What’s Vulnerable › Vulnerabilities

CVE-2026-68162: sctp: avoid auth_enable sysctl UAF during netns teardown

• Severity: high (CVSS 7.8 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.2% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2026-08-10 · updated 2026-10-19
• Weakness: CWE-416

Description

In the Linux kernel, the following vulnerability has been resolved: sctp: avoid auth_enable sysctl UAF during netns teardown proc_sctp_do_auth() updates the SCTP control socket after changing net.sctp.auth_enable. The handler gets the per-net SCTP state from ctl->data, so an already opened sysctl file can still target a network namespace while that namespace is being torn down. SCTP previously registered its per-net sysctls from sctp_defaults_init(), while the control socket is created later from sctp_ctrlsock_init(). This exposed a window during initialization where auth_enable was writable before net->sctp.ctl_sock existed, and a teardown window where auth_enable stayed writable after inet_ctl_sock_destroy() had released the control socket. Move the per-net SCTP sysctl registration into sctp_ctrlsock_init() after sctp_ctl_sock_init() succeeds, and unregister the sysctl table before destroying the control socket in sctp_ctrlsock_exit(). If sysctl registration fails after the control socket was created, destroy the control socket in the same init path. Make sctp_sysctl_net_unregister() tolerate a missing header and clear the saved pointer so init-error and exit paths can safely share the unregister helper.

Affected products

• Linux kernel: from 5.4.290 before 5.4.292; from 5.10.234 before 5.10.266; from 5.15.177 before 5.15.217; from 6.1.125 before 6.1.184; from 6.6.72 before 6.6.151; from 6.12.10 before 6.12.101 — fixed in 5.10.266, 5.15.217, 5.4.292, 6.1.184, 6.12.101, 6.6.151

How to fix

Upgrade to a fixed version: Linux kernel 5.10.266, 5.15.217, 5.4.292, 6.1.184. Check the vendor advisory for mitigations.

References

• https://git.kernel.org/stable/c/158f3cc332dc53f43ec20060233d7c3cecd6d912
• https://git.kernel.org/stable/c/19573dcddb8819fd68d6cd1f916c1c99c3fa4ff4
• https://git.kernel.org/stable/c/626bda8cfe43dff19a9833ff6ba055a817b5455c
• https://git.kernel.org/stable/c/66700c0719675e0e118ae83b2d7168dacd69dd3d
• https://git.kernel.org/stable/c/a50e73488e0bbdd262b3be3c9a1d8dd078382381
• https://git.kernel.org/stable/c/be6aae9d1b91c603adb35872d37d40e83daf8758
• https://git.kernel.org/stable/c/ceb7190b5c873d4a1267a1600c5aa52c600e929f
• https://git.kernel.org/stable/c/f8d5e7846025f4ab15a461235f8ebae9094a361a
• https://git.kernel.org/stable/c/fd66854a22661929245f3d2b244c432bc8b1a150

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