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-2021-33656

CVE-2021-33656MEDIUM

n/a openEuler:kernel — When setting font with malicous data by ioctl cmd PIO_FONT,kernel will write memory out of bounds.

  AV  AC  PR  UI  S  C  I  A   CVSS    EPSS   %ile   KEV
   P   L   N   N  U  H  H  H    6.8   .0061   48.2     —

AFFECTED
  Product           Versions     Fixed
  openEuler:kernel  <5.10.127 –  —

TIMELINE
  May 28  Reserved by openEuler
  Jul 18  Published (CNA: openEuler)
  Oct 8   ENRICHED — CVE-2021-33656 (openEuler:kernel). Received CVSS 6.8 and CPE data from NVD.

CWE-787 · CNA: openEuler · CVSS v3.1 · 4 references · NVD status: Modified

Description

When setting font with malicous data by ioctl cmd PIO_FONT,kernel will write memory out of bounds.

Lifecycle

Complete event history — 3 events, chronological
Date	Event	Detail
May 28, 2021	Reserved	Reserved by openEuler
July 18, 2022	Published	Published (CNA: openEuler)
October 8, 2026	ENRICHED	ENRICHED — CVE-2021-33656 (openEuler:kernel). Received CVSS 6.8 and CPE data from NVD.

Affected

Affected products and packages — 1 row
Vendor	Product / Package	Ecosystem	Version introduced	Fixed
n/a	openEuler:kernel	—	<5.10.127	—

Weaknesses

CWE-787

References (4)

http://www.openwall.com/lists/oss-security/2022/07/19/3 [Mailing List, Patch, Third Party Advisory]
https://git.kernel.org/pub/scm/linux/kernel/git/stable/stable-queue.git/tree/releases/5.10.127/vt-drop-old-font-ioctls.patch [Patch, Third Party Advisory]
https://lists.debian.org/debian-lts-announce/2022/10/msg00000.html [Mailing List, Third Party Advisory]
https://www.openeuler.org/en/security/cve/detail.html?id=CVE-2021-33656&packageName=kernel [Third Party Advisory]

Authoritative record: CVE-2021-33656 at cve.org

Weaknesses: CWE-787

About this page

This is a reference page, not a dated page of record. It assembles the complete lifecycle of CVE-2021-33656 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.