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-2021-20320

CVE-2021-20320MEDIUM

n/a kernel — A flaw was found in s390 eBPF JIT in bpf_jit_insn in arch/s390/net/bpf_jit_comp.c in the Linux kernel.

  AV  AC  PR  UI  S  C  I  A   CVSS    EPSS   %ile   KEV
   L   L   L   N  U  H  N  N    5.5   .0026   16.6     —

AFFECTED
  Product  Versions           Fixed
  kernel   kernel 5.15 rc3 –  —

TIMELINE
  Dec 17  Reserved by redhat
  Feb 18  Published (CNA: redhat)
  Oct 8   ENRICHED — CVE-2021-20320 (kernel). Received CVSS 5.5 and CPE data from NVD.

CWE-200 · CNA: redhat · CVSS v3.1 · 2 references · NVD status: Modified

Description

A flaw was found in s390 eBPF JIT in bpf_jit_insn in arch/s390/net/bpf_jit_comp.c in the Linux kernel. In this flaw, a local attacker with special user privilege can circumvent the verifier and may lead to a confidentiality problem.

Lifecycle

Complete event history — 3 events, chronological
Date	Event	Detail
December 17, 2020	Reserved	Reserved by redhat
February 18, 2022	Published	Published (CNA: redhat)
October 8, 2026	ENRICHED	ENRICHED — CVE-2021-20320 (kernel). Received CVSS 5.5 and CPE data from NVD.

Affected

Affected products and packages — 1 row
Vendor	Product / Package	Ecosystem	Version introduced	Fixed
n/a	kernel	—	kernel 5.15 rc3	—

Weaknesses

CWE-200

References (2)

https://bugzilla.redhat.com/show_bug.cgi?id=2010090 [Issue Tracking, Third Party Advisory]
https://lore.kernel.org/bpf/20210902185229.1840281-1-johan.almbladh%40anyfinetworks.com/

Authoritative record: CVE-2021-20320 at cve.org

Weaknesses: CWE-200

About this page

This is a reference page, not a dated page of record. It assembles the complete lifecycle of CVE-2021-20320 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.