Auth bypass in Linux Kernel
CVE-2020-27777
A flaw was found in the way RTAS handled memory accesses in userspace to kernel communication. On a locked down (usually due to Secure Boot) guest system running on top of PowerVM or KVM hypervisors (pseries platform) a root like local user could use this flaw to further increase their privileges to that of a running kernel.
Vulnerability class: Broken Access Control
EPSS: 0.005 (40.0th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 6.7 (Medium). Vector: CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H.
Affected products
- Linux Linux_kernel
- Redhat Enterprise_linux — versions 5.0, 6.0, 7.0
- Redhat Openshift_container_platform — versions 4.4, 4.5, 4.6
- N/a Kernel — versions kernel 5.10-rc1
Weakness classification (CWE)
Public proof-of-concept exploits
References
- secalert@redhat.com (Patch, Third Party Advisory, x_refsource_MISC, Issue Tracking)
- secalert@redhat.com (Exploit, Patch, Mailing List, Third Party Advisory, x_refsource_MISC)
- secalert@redhat.com (Mailing List, Third Party Advisory, x_refsource_MISC)
- secalert@redhat.com (Exploit, Patch, x_refsource_MISC, Vendor Advisory)
Frequently asked questions
- What is CVE-2020-27777?
- CVE-2020-27777 is a medium-severity vulnerability in Linux Kernel, classified under Missing Authorization. CVSS score: 6.7/10. Published 2020-12-15.
- How severe is CVE-2020-27777?
- Medium severity. CVSS v3 base score is 6.7 out of 10.
- Is CVE-2020-27777 known to be exploited?
- 1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.