Vulnerability in Linux Kernel
CVE-2023-4155
A flaw was found in KVM AMD Secure Encrypted Virtualization (SEV) in the Linux kernel. A KVM guest using SEV-ES or SEV-SNP with multiple vCPUs can trigger a double fetch race condition vulnerability and invoke the `VMGEXIT` handler recursively. If an attacker manages to call the handler multiple times, they can trigger a stack overflow and cause a denial of service or potentially guest-to-host escape in kernel configurations without stack guard pages (`CONFIG_VMAP_STACK`).
Vulnerability class: TOCTOU (Time-of-Check to Time-of-Use)
Published · last modified .
CVSS v3 metric
CVSS v3 base score 5.3 (Medium). Vector: CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:C/C:N/I:N/A:H.
EPSS exploit prediction
EPSS: 0.002 (5.6th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 6th percentile — 5.6% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.002 · newest: 0.002 · change: 0.000
Affected products
- Linux Kernel
- Fedora
- 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
- Red Hat Enterprise Linux — versions 8.0, 9.0
- Kernel
Weakness classification (CWE)
References
- access.redhat.com/security/cve/CVE-2023-4155 (Third Party Advisory, vdb-entry)
- bugzilla.redhat.com/show_bug.cgi (issue-tracking, Patch, Third Party Advisory, Issue Tracking)
Frequently asked questions
- What is CVE-2023-4155?
- CVE-2023-4155 is a medium-severity vulnerability in Linux Kernel, classified under Time-of-check Time-of-use (TOCTOU) Race Condition. CVSS score: 5.3/10. Published 2023-09-13.
- How severe is CVE-2023-4155?
- Medium severity. CVSS v3 base score is 5.3 out of 10.