CVE-2023-4194

Summary

A flaw was found in the Linux kernel's TUN/TAP functionality. This issue could allow a local user to bypass network filters and gain unauthorized access to some resources. The original patches fixing CVE-2023-1076 are incorrect or incomplete. The problem is that the following upstream commits - a096ccca6e50 ("tun: tun_chr_open(): correctly initialize socket uid"), - 66b2c338adce ("tap: tap_open(): correctly initialize socket uid"), pass "inode->i_uid" to sock_init_data_uid() as the last parameter and that turns out to not be accurate.

Impact & exploitability

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N

Affected products we track (4)

Recommendation

Apply the vendor fix in your normal patch cycle. Open any affected product above for its exact safe version.

Official patch: https://lore.kernel.org/all/20230731164237.48365-1-lersek@redhat.com/ ↗

Additional information

• NVD record
• https://lore.kernel.org/all/20230731164237.48365-1-lersek@redhat.com/Patch
• https://lore.kernel.org/all/20230731164237.48365-2-lersek@redhat.com/Patch
• https://lore.kernel.org/all/20230731164237.48365-3-lersek@redhat.com/Patch
• https://access.redhat.com/errata/RHSA-2023:6583Advisory
• https://access.redhat.com/security/cve/CVE-2023-4194Advisory
• https://bugzilla.redhat.com/show_bug.cgi?id=2229498Advisory