Vulnerability in Apple macOS
CVE-2026-21218
Improper handling of missing special element in .NET allows an unauthorized attacker to perform spoofing over a network.
Published · last modified .
CVSS v3 metric
CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N.
EPSS exploit prediction
EPSS: 0.010 (62.9th percentile), scored .
Low probability of exploitation in the next 30 days, but still tracked. 63rd percentile — 62.9% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.010 · newest: 0.010 · change: -0.000
Affected products
- Apple macOS
- Linux Kernel
- Microsoft .Net
- Microsoft .Net 10.0 — versions 10.0.0
- Microsoft .Net 8.0 — versions 8.0.0
- Microsoft .Net 9.0 — versions 9.0.0
- Microsoft Windows
Weakness classification (CWE)
References
- .NET Spoofing Vulnerability (vendor-advisory, patch, Vendor Advisory)
Frequently asked questions
- What is CVE-2026-21218?
- CVE-2026-21218 is a high-severity vulnerability in Apple macOS, classified under CWE-166. CVSS score: 7.5/10. Published 2026-02-10.
- How severe is CVE-2026-21218?
- High severity. CVSS v3 base score is 7.5 out of 10.