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.
Published · last modified .
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.
EPSS exploit prediction
EPSS: 0.003 (17.3th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 17th percentile — 17.3% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.003 · newest: 0.003 · change: -0.000
Affected products
- Linux Kernel — versions 6.5
- Debian Linux — versions 10.0, 11.0, 12.0
- Fedoraproject Fedora — versions 37, 38
- Red Hat Enterprise Linux 6
- Red Hat Enterprise Linux 7
- Red Hat Enterprise Linux 8
- Red Hat Enterprise Linux 9 — versions 0:5.14.0-362.8.1.el9_3
- Red Hat Virtualization 4
- Red Hat Enterprise Linux — versions 8.0, 9.0
Weakness classification (CWE)
Public proof-of-concept exploits
References
- access.redhat.com/errata/RHSA-2023:6583 (vendor-advisory, Third Party Advisory)
- access.redhat.com/security/cve/CVE-2023-4194 (Third Party Advisory, vdb-entry)
- bugzilla.redhat.com/show_bug.cgi (issue-tracking, Third Party Advisory, Issue Tracking)
- lore.kernel.org/all/20230731164237.48365-1-lersek@redhat.com/ (Patch, Mailing List, Vendor Advisory)
- lore.kernel.org/all/20230731164237.48365-2-lersek@redhat.com/ (Patch, Mailing List, Vendor Advisory)
- lore.kernel.org/all/20230731164237.48365-3-lersek@redhat.com/ (Patch, Mailing List, Vendor Advisory)
- af854a3a-2127-422b-91ae-364da2661108
- af854a3a-2127-422b-91ae-364da2661108
- af854a3a-2127-422b-91ae-364da2661108
- af854a3a-2127-422b-91ae-364da2661108
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.