Hallmark — Cyber Attacks, Breaches & Threat Activity

Threat entity extracted from intelligence sources

Frequency
4
occurrences
First Seen
April 14, 2026
Last Seen
April 16, 2026

Hallmark is a organization tracked across 2 threat clusters and 4 intelligence report mentions on ThreatCluster. First observed April 14, 2026; most recent activity April 16, 2026.

Related Threat Clusters

  • Malicious LLM Proxy Routers Compromise AI Security

    A recent study identified 28 malicious LLM proxy routers that can modify AI service responses and access sensitive credentials. The research tested 28 paid routers and 400 free routers, revealing that nine injected…

    2 articles · Updated April 15, 2026
  • ShinyHunters Target SSO Accounts in Voice Phishing Attacks

    The ShinyHunters extortion gang has claimed responsibility for a series of voice phishing attacks targeting single sign-on (SSO) accounts at major platforms including Okta, Microsoft, and Google. In these attacks,…

    162 articles · Updated January 25, 2026

Recent Intelligence Reports

  • Amtrak allegedly breached by ShinyHunters, massive data leak threatened — Scworld · April 16, 2026
  • 1.7 million — haveibeenpwned.com · April 15, 2026
  • Malicious LLM proxy routers found in the wild — News.Risky.Biz · April 15, 2026
  • Hackers threaten to leak over 9M Amtrak records, including personal info — Cybernews · April 14, 2026

CVSS v3.1 Breakdown