onyx

onyx --cves cve-2021-44223

CVE-2021-44223

HIGHPOCWordPress
score
<0.1
cvss
8.1
epss
29.0%
published
2021-11-25
kev added
—
first seen

WordPress before 5.8 lacks support for the Update URI plugin header, enabling remote attackers to execute arbitrary code via supply-chain attacks on plugins with valid slugs not yet in the WordPress.org Plugin Directory, exploit requires the plugin to have a valid slug and be used in the installation.

Timeline

How this CVE moved toward exploitation. Chart: last 30 days — trend score, EPSS, community mentions per day; hover the event lane.

events2021-11-25 — PublishedP2026-10-21 — Tracked by OnyxT2026-10-21 — Public PoCXscore2026-10-21: score <0.1<0.1epss2026-09-22: epss 29.0%2026-09-23: epss 29.0%2026-09-24: epss 29.0%2026-09-25: epss 29.0%2026-09-26: epss 29.0%2026-09-27: epss 29.0%2026-09-28: epss 29.0%2026-09-29: epss 29.0%2026-09-30: epss 29.0%2026-10-01: epss 29.0%2026-10-02: epss 29.0%2026-10-03: epss 29.0%2026-10-04: epss 29.0%2026-10-05: epss 29.0%2026-10-06: epss 29.0%2026-10-07: epss 29.0%2026-10-08: epss 29.0%2026-10-09: epss 29.0%2026-10-10: epss 29.0%2026-10-11: epss 29.0%2026-10-12: epss 29.0%2026-10-13: epss 29.0%2026-10-14: epss 29.0%2026-10-15: epss 29.0%2026-10-16: epss 29.0%2026-10-18: epss 29.0%2026-10-19: epss 29.0%2026-10-20: epss 29.0%2026-10-21: epss 29.0%29.0%mentions/day0no mentions in 30 days2026-09-22today
  1. Published
  2. Tracked by Onyx
  3. Public PoC

Exploit availability

Public PoC flagged by vulnx; no direct exploit link among the citations.

Weaknesses

NVD-CWE-Other

References 2