APT23

THREAT ACTOR PROFILE

APT23

Tropic Trooper

APT23 is a Chinese-speaking espionage group active since 2011, best known as Tropic Trooper and KeyBoy. It targets government, healthcare, transportation and high-tech sectors across Taiwan, the Philippines, Hong Kong and, more recently, the Middle East. In 2026 it adopted the AdaptixC2 framework and a trojanized SumatraPDF loader against Chinese-speaking users in Taiwan, South Korea and Japan.

China

Government / High-tech

First seen

2011

Latest IOC

IP indicators

Hosts

SHA256 hashes

Posts

TABLE OF CONTENTS

Names and aliases

Group profile

Attack lifecycle

Malware and tooling

IOCs

Notable campaigns

NAMES AND ALIASES

APT23, Tropic Trooper and KeyBoy

APT23 is tracked under many vendor names tied to its long history. It maps to one entry among the the APT groups we profile, and its regional targeting overlaps with China-aligned crews like BlackTech.

GROUP PROFILE

Long-running espionage across Asia and beyond

APT23 is a durable Chinese-speaking espionage actor. Over more than a decade it has refined spearphishing and web-shell tradecraft while steadily updating its malware, and it has expanded beyond its traditional Asia-Pacific footprint into the Middle East.

Our record places its origin as China and ties it to espionage across government and high-tech sectors. A 2026 Zscaler-tracked campaign hit Chinese-speaking users in Taiwan and individuals in South Korea and Japan.

The group's recent chain uses a trojanized SumatraPDF in ZIP lures to run a modified TOSHIS loader, which fetches a decoy PDF and an AdaptixC2 Beacon from attacker and GitHub infrastructure.

Facts:

Initial Access

Russian Federation · GRU

Initial Access

Russian Federation · GRU

Initial Access

Russian Federation · GRU

Initial Access

Russian Federation · GRU

Victims reported in our records and posts:

ATTACK LIFECYCLE

Trojanized SumatraPDF into AdaptixC2

The stages below come from APT23 and Tropic Trooper activity in posts we track on our IOC Hunter feed.

Initial Access

Spear-phishing remains the front door. In the 2026 campaign Hunt.io tracked as Operation Neusploit, APT28 sent convincing spear-phishing from already-compromised government accounts and abused a Microsoft Office security bypass (CVE-2026-21509) to kick off a fileless chain. A separate June 2026 cluster delivered the LameHug malware through spear-phishing ZIP archives using double-extension lures.

Initial Access

MALWARE AND TOOLING

AdaptixC2, TOSHIS and EntryShell

Initial Access

CVES EXPLOITED

ProxyShell and ColdFusion in earlier intrusions

CVE-2026-21509

A Microsoft Office security bypass used to open the fileless chain in Operation Neusploit, and again in the PixyNetLoader intrusion chain. Both campaigns paired the exploit with spear-phishing from compromised accounts rather than mass exploitation.

CVE-2026-21509

APT23

IOCS FROM HUNT.IO PLATFORM

Latest IOCs

We currently track - IP indicators, - hosts, and - SHA256 hashes for Akira across - intelligence posts, with the most recent indicator dated -. The sample below is limited to indicators from the latest posts. It is not the full set.

Showing a sample of recent indicators

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APT23

IOC set, full IP, host and hash history.

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Showing a sample of recent indicators

Get the complete

APT23

IOC set, full IP, host and hash history.

Unlock all the IOCs for Free

NOTABLE CAMPAIGNS

AdaptixC2 and the SumatraPDF loader

Recent reporting tracks the group's 2026 tooling shift.

PixyNetLoader tracking

A clustering of roughly 90 loader samples across four sub-families from 2024 to 2026, with steganography and cloud C2, also linking to related APT28 tooling such as SlimAgent and Graphite.

PixyNetLoader tracking

A clustering of roughly 90 loader samples across four sub-families from 2024 to 2026, with steganography and cloud C2, also linking to related APT28 tooling such as SlimAgent and Graphite.

PixyNetLoader tracking

A clustering of roughly 90 loader samples across four sub-families from 2024 to 2026, with steganography and cloud C2, also linking to related APT28 tooling such as SlimAgent and Graphite.

PixyNetLoader tracking

A clustering of roughly 90 loader samples across four sub-families from 2024 to 2026, with steganography and cloud C2, also linking to related APT28 tooling such as SlimAgent and Graphite.