Auth bypass in Linux Kernel

CVE-2023-4194

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.

EPSS: 0.003 (19.6th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 5.5 (Medium). Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N.

Affected products

Weakness classification (CWE)

Public proof-of-concept exploits

References

Frequently asked questions

What is CVE-2023-4194?
CVE-2023-4194 is a medium-severity vulnerability in Linux Kernel, classified under Access of Resource Using Incompatible Type (Type Confusion). CVSS score: 5.5/10. Published 2023-08-07.
How severe is CVE-2023-4194?
Medium severity. CVSS v3 base score is 5.5 out of 10.
Is CVE-2023-4194 known to be exploited?
1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.