Zero-day report: November 2026 (so far)

CISA added 1 exploited vulnerability to its catalog in November 2026 so far. 1 was a zero-day, listed within a week of going public. The most-hit vendor was WordPress, with 1.

1exploited flaws added

1zero-days

0used by ransomware

1vendors affected

By technology

Websites & online stores1
Phones & computers0
Web browsers0
Office, email & file sharing0
Firewalls, VPNs & network gear0
Remote access & IT tools0
Servers, cloud & backup0
Developer, data & AI tools0
Other business software0

Most-hit vendors

WordPress1

Every flaw added in November 2026

WordPress · WordPress CoreWordPress WordPress Core Time-of-check Time-of-use (TOCTOU) Race Condition VulnerabilityCVE-2026-119977 · Nov 3, 2026 · zero-day

Source: CISA's Known Exploited Vulnerabilities catalog, by the date CISA added each flaw. Ransomware use is CISA's flag.