Reference page — cumulative record through Monday, October 19, 2026 UTC. Reference pages update as the archive grows; only dated daily editions are immutable pages of record.

CVE-2020-27171

CVE-2020-27171MEDIUM

n/a n/a — An issue was discovered in the Linux kernel before 5.11.8.

  AV  AC  PR  UI  S  C  I  A   CVSS    EPSS   %ile   KEV
   L   L   H   N  U  H  N  H    6.0   .0058   46.4     —

AFFECTED
  Product  Versions  Fixed
  n/a      n/a –     —

TIMELINE
  Oct 16  Reserved by mitre
  Mar 20  Published (CNA: mitre)
  Oct 8   ENRICHED — CVE-2020-27171. Received CVSS 6.0 and CPE data from NVD.

CWE-193 · CNA: mitre · CVSS v3.1 · 9 references · NVD status: Modified

Description

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.

Lifecycle

Complete event history — 3 events, chronological
Date	Event	Detail
October 16, 2020	Reserved	Reserved by mitre
March 20, 2021	Published	Published (CNA: mitre)
October 8, 2026	ENRICHED	ENRICHED — CVE-2020-27171. Received CVSS 6.0 and CPE data from NVD.

Affected

Affected products and packages — 1 row
Vendor	Product / Package	Ecosystem	Version introduced	Fixed
n/a	n/a	—	n/a	—

Weaknesses

CWE-193

References (9)

http://packetstormsecurity.com/files/162117/Kernel-Live-Patch-Security-Notice-LSN-0075-1.html [Third Party Advisory, VDB Entry]
http://www.openwall.com/lists/oss-security/2021/03/24/5 [Mailing List, Third Party Advisory]
https://cdn.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.11.8 [Patch, Vendor Advisory]
https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf.git/patch/?id=10d2bb2e6b1d8c4576c56a748f697dbeb8388899 [Patch, Vendor Advisory]
https://lists.debian.org/debian-lts-announce/2021/03/msg00035.html [Mailing List, Third Party Advisory]
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/FB6LUXPEIRLZH32YXWZVEZAD4ZL6SDK2/
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/QRTPQE73ANG7D6M4L4PK5ZQDPO4Y2FVD/
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/T2S3I4SLRNRUQDOFYUS6IUAZMQNMPNLG/
https://www.openwall.com/lists/oss-security/2021/03/19/3 [Mailing List, Patch, Third Party Advisory]

Authoritative record: CVE-2020-27171 at cve.org

Weaknesses: CWE-193

About this page

This is a reference page, not a dated page of record. It assembles the complete lifecycle of CVE-2020-27171 from the CVE Program record, NVD enrichment, the CISA KEV catalog, EPSS, and OSV advisories. The box score's numbers (CVSS, EPSS, KEV status) are current as of Monday, October 19, 2026 UTC and are re-derived as the archive grows; only dated daily editions are immutable pages of record. The authoritative source for this identifier is cve.org.