Use After Free in Linux Kernel
CVE-2023-3776
A use-after-free vulnerability in the Linux kernel's net/sched: cls_fw component can be exploited to achieve local privilege escalation. If tcf_change_indev() fails, fw_set_parms() will immediately return an error after incrementing or decrementing the reference counter in tcf_bind_filter(). If an attacker can control the reference counter and set it to zero, they can cause the reference to be freed, leading to a use-after-free vulnerability. We recommend upgrading past commit 0323bce598eea038714f941ce2b22541c46d488f.
Vulnerability class: Use-After-Free
EPSS: 0.005 (40.4th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 7.8 (High). Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.
Affected products
- Linux Kernel — versions 2.6
- Linux Linux_kernel — versions 6.5
- Debian Debian_linux — versions 10.0, 11.0, 12.0
Weakness classification (CWE)
Public proof-of-concept exploits
References
- cve-coordination@google.com (Patch, Mailing List, patch, Vendor Advisory)
- cve-coordination@google.com (Patch, Vendor Advisory)
- cve-coordination@google.com (Third Party Advisory)
- cve-coordination@google.com (Third Party Advisory)
- cve-coordination@google.com (VDB Entry, Third Party Advisory)
- cve-coordination@google.com (Mailing List, Third Party Advisory)
- cve-coordination@google.com (VDB Entry, Third Party Advisory)
- cve-coordination@google.com (Mailing List, Third Party Advisory)
- cve-coordination@google.com (Third Party Advisory)
Frequently asked questions
- What is CVE-2023-3776?
- CVE-2023-3776 is a high-severity vulnerability in Linux Kernel, classified under Use After Free. CVSS score: 7.8/10. Published 2023-07-21.
- How severe is CVE-2023-3776?
- High severity. CVSS v3 base score is 7.8 out of 10.
- Is CVE-2023-3776 known to be exploited?
- 4 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.