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
Published · last modified .
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.
EPSS exploit prediction
EPSS: 0.005 (41.4th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 41st percentile — 41.4% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.005 · newest: 0.005 · change: 0.000
Affected products
- Linux Kernel — versions 2.6
- Linux Kernel — versions 6.5
- Debian Linux — versions 10.0, 11.0, 12.0
Weakness classification (CWE)
Public proof-of-concept exploits
References
- git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit (Patch, Mailing List, patch, Vendor Advisory)
- kernel.dance/0323bce598eea038714f941ce2b22541c46d488f (Patch, Vendor Advisory)
- www.debian.org/security/2023/dsa-5480 (Third Party Advisory)
- www.debian.org/security/2023/dsa-5492 (Third Party Advisory)
- packetstormsecurity.com/files/175072/Kernel-Live-Patch-Security-Notice-LSN-0098… (VDB Entry, Third Party Advisory)
- lists.debian.org/debian-lts-announce/2023/10/msg00027.html (Mailing List, Third Party Advisory)
- packetstormsecurity.com/files/175963/Kernel-Live-Patch-Security-Notice-LSN-0099… (VDB Entry, Third Party Advisory)
- lists.debian.org/debian-lts-announce/2024/01/msg00004.html (Mailing List, Third Party Advisory)
- security.netapp.com/advisory/ntap-20240202-0003/ (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?
- 5 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.