Vulnerability in Linux Kernel
CVE-2020-27171
An issue was discovered in the Linux kernel before 5.11.8. kernel/bpf/verifier.c has an off-by-one error (with a resultant integer underflow) affecting out-of-bounds speculation on pointer arithmetic, leading to side-channel attacks that defeat Spectre mitigations and obtain sensitive information from kernel memory, aka CID-10d2bb2e6b1d.
Published · last modified .
CVSS v3 metric
CVSS v3 base score 6.0 (Medium). Vector: CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:H/I:N/A:H.
EPSS exploit prediction
EPSS: 0.006 (45.4th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 45th percentile — 45.4% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.006 · newest: 0.006 · change: 0.000
Affected products
- Linux Kernel
- Canonical Ubuntu Linux — versions 14.04, 16.04, 18.04
- Debian Linux — versions 9.0
- Fedoraproject Fedora — versions 32, 33, 34
Weakness classification (CWE)
Public proof-of-concept exploits
References
- cdn.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.11.8 (Patch, Vendor Advisory)
- www.openwall.com/lists/oss-security/2021/03/19/3 (Patch, Mailing List, Third Party Advisory)
- git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf.git/patch/ (Patch, Vendor Advisory)
- lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/… (vendor-advisory)
- lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/… (vendor-advisory)
- www.openwall.com/lists/oss-security/2021/03/24/5 (mailing-list, Mailing List, Third Party Advisory)
- lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/… (vendor-advisory)
- lists.debian.org/debian-lts-announce/2021/03/msg00035.html (mailing-list, Mailing List, Third Party Advisory)
- packetstormsecurity.com/files/162117/Kernel-Live-Patch-Security-Notice-LSN-0075… (VDB Entry, Third Party Advisory)
Frequently asked questions
- What is CVE-2020-27171?
- CVE-2020-27171 is a medium-severity vulnerability in Linux Kernel, classified under Off-by-one Error. CVSS score: 6.0/10. Published 2021-03-20.
- How severe is CVE-2020-27171?
- Medium severity. CVSS v3 base score is 6.0 out of 10.
- Is CVE-2020-27171 known to be exploited?
- 1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.