CVE-2021-28799

Exploited in the Wild ✓ Confirmed 0-Day
Triaged: March 5, 2026 1 article
VulnLookup ↗ NVD ↗ MITRE ↗ CISA KEV ↗

EPSS Score

Source: FIRST.org · 2026-05-24
90.84%
probability
This CVE has a 90.84% probability of being exploited in the next 30 days.
0% Top 99.6th percentile of all CVEs 100%
CVSS score unavailable
Neither CIRCL nor NVD returned a CVSS score for this CVE. View on VulnerabilityLookup ↗

Attack Intelligence

Signal Intelligence

Confidenceⓘ
85%
EPSS 90.84%
Mentions 1
Last Seen Oct 29, 2024

CNA Information

Analyst Note

CVE-2021-28799 was explicitly named as a zero-day exploited at Pwn2Own (a live hacking competition where vulnerabilities are exploited against unpatched systems before patches exist). The BleepingComputer article title directly confirms 'zero-day exploited at Pwn2Own,' establishing exploitation preceded patch availability. QNAP's patch release on 2021-05-13 aligns with CVE publication, confirming vendor coordinated disclosure of an actively exploited vulnerability.

Triage Info

Decided atMar 05, 2026