NULL pointer dereference in Linux Kernel
CVE-2021-4095
A NULL pointer dereference was found in the Linux kernel's KVM when dirty ring logging is enabled without an active vCPU context. An unprivileged local attacker on the host may use this flaw to cause a kernel oops condition and thus a denial of service by issuing a KVM_XEN_HVM_SET_ATTR ioctl. This flaw affects Linux kernel versions prior to 5.17-rc1.
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:N/A:H.
EPSS exploit prediction
EPSS: 0.004 (30.3th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 30th percentile — 30.3% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.004 · newest: 0.004 · change: 0.000
Affected products
- Linux Kernel
- Fedoraproject Fedora — versions 34, 35
- Kernel — versions Linux kernel versions prior to 5.17-rc1
Weakness classification (CWE)
References
- www.openwall.com/lists/oss-security/2022/01/17/1 (mailing-list, Exploit, Patch, Mailing List, Third Party Advisory)
- bugzilla.redhat.com/show_bug.cgi (Exploit, Patch, Third Party Advisory, Issue Tracking)
- lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/… (vendor-advisory)
- lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/… (vendor-advisory)
Frequently asked questions
- What is CVE-2021-4095?
- CVE-2021-4095 is a medium-severity vulnerability in Linux Kernel, classified under NULL Pointer Dereference. CVSS score: 5.5/10. Published 2022-03-10.
- How severe is CVE-2021-4095?
- Medium severity. CVSS v3 base score is 5.5 out of 10.