VulnPulse

← Threat Actor Index

APT27

aka Linen Typhoon, Emissary Panda, LuckyMouse, Iron Tiger, Bronze Union, Threat Group-3390

Espionage

A Chinese espionage group active since around 2010 that steals government and defense information and intellectual property. In 2025 it was seen joining attacks on a SharePoint weakness.

Alert level
2/ 5
Reports & advisories (90 days)
0
Known exploited CVEs
3
Personal data leaked (disclosed)
None confirmed

Attribution

  • Assessed as a Chinese state actor (Linen Typhoon) — Microsoft
  • Charged two APT27 members, alleging they sold stolen data to customers tied to the Chinese government — US Department of Justice

Exploited vulnerabilities and targeted products

Microsoft

CVE-2025-53770 CVE-2025-53771 CVE-2025-49704 CVE-2025-49706

If you run any of these products, first make sure they are updated to a fixed version.

How they attack

Entry

Exploiting on-premises servers

Like exploiting a flaw in the lock on the office's shared filing cabinet (SharePoint) to open the whole thing.

Entry

Booby-trapping websites targets visit

Like poisoning the watering hole that the prey visits every day and waiting.

Inside

Planting small back doors on web servers

Like leaving a tiny copied key in the shop's back-door lock that only the intruder knows about.

Goal

Stealing and selling secrets

Like an industrial spy who passes stolen blueprints to whoever will pay for them.

Sources

Attributions are quoted as assessed by governments and security vendors. VulnPulse does not make attributions itself.

Leak counts only add up figures disclosed by the affected companies or authorities, never the attackers' own claims. We do not list victim names or link to leak sites.

The alert level is calculated automatically from reports and advisories in the last 90 days, known exploited vulnerabilities, and whether the group has targeted Japan.

Updated 2026-10-23 · daily