Phish and Chips: China-Aligned Espionage Actors Ramp Up Taiwan Semiconductor Industry Targeting 

SecurityVendor

Key findings 

Between March and June 2025, Proofpoint Threat Research observed three Chinese state-sponsored threat actors conduct targeted phishing campaigns against the Taiwanese semiconductor industry. In all cases, the motive was most likely espionage. 
Targets of these campaigns ranged from organizations involved in the manufacturing, design, and testing of semiconductors and integrated circuits, wider equipment and services supply chain entities within this sector, as well as financial investment analysts specializing in the Taiwanese semiconductor market. 
This activity likely reflects China’s strategic priority to achieve semiconductor self-sufficiency and decrease reliance on international supply chains and technologies, particularly in light of US and Taiwanese export controls. 

Overview 

Analyst note: Proofpoint uses the UNK_ designator to define clusters of activity that are still developing and have not been observed for long enough to receive a numerical TA designation. 

China-aligned threat actors have routinely targeted the semiconductor industry for many years. This activity likely aligns with China’s internal strategic economic priorities, which have increasingly emphasized the importance of semiconductor technologies in successive national economic development initiatives, including the Five-Year Plans. A growing focus on ensuring strategic self-reliance for semiconductor technologies, accelerated by external pressures from export controls, has likely reinforced the priority of intelligence collection operations directed at this industry. This is reflected in China-aligned espionage activity tracked by the Proofpoint Threat Research team, where we are currently observing an elevated level of targeting of the industry by China-aligned groups compared to historical activity.

Between March and June 2025, Proofpoint identified multiple China-aligned threat actors specifically targeting Taiwanese organizations within the semiconductor industry. This included a China-aligned threat actor tracked as UNK_FistBump targeting semiconductor design, manufacturing, and supply chain organizations in employment-themed phishing campaigns resulting in the delivery of Cobalt Strike or the custom Voldemort backdoor.  

Additionally, Proofpoint observed another China-aligned threat actor tracked as UNK_DropPitch targeting individuals in multiple major investment firms who specialize in investment analysis specifically within the Taiwanese semiconductor industry. This UNK_DropPitch targeting is exemplary of intelligence collection priorities spanning less obvious areas of the semiconductor ecosystem beyond just design and manufacturing entities. Finally, we also observed an actor tracked as UNK_SparkyCarp conducting credential phishing activity against a Taiwanese semiconductor company using a custom Adversary in the Middle (AiTM) phishing kit.

UNK_FistBump targets semiconductor manufacturing and supply chain with job seeking lures 

In May and June 2025, Proofpoint observed UNK_FistBump conducting multiple spearphishing campaigns targeting Taiwan-based semiconductor manufacturing, packaging, testing, and supply chain organizations. Posing as a graduate student seeking employment, the actor used compromised Taiwanese university email addresses to send their phishing email to recruitment and HR personnel. Subject lines observed across this activity include the following: 

產品工程(材料分析/製程優化)-台灣大學-薛豪 [附履歷] (Machine Translation: Product Engineering (Material Analysis/Process Optimization) – National Taiwan University – Xue Hao [with resume]) 
Bumping工程師-台灣大學-材料工程學類-薛豪 (Machine Translation: Bumping Engineer-National Taiwan University-Material Engineering-Xue Hao) 
【重要】麻煩協助確認 (Machine translation: [Important] Please help confirm) 

Example UNK_FistBump job application phishing email (machine translated from Traditional Chinese). 

Delivery 

UNK_FistBump phishing emails were sent via a likely compromised account and contained either a password-protected archive attachment or a PDF attachment. The PDF attachments contained URLs leading to an archive file hosted on either a Zendesk instance or the Filemail file sharing service. Earlier UNK_FistBump campaigns delivered a Cobalt Strike Beacon payload, but the group shifted to delivery of the custom Voldemort backdoor in late May 2025. 

UNK_FistBump PDF attachment leading to file sharing site (machine translated from Traditional Chinese). 

In an unusual campaign in late May 2025, UNK_FistBump included two distinct infection chains beginning with the same password-protected archive, one of which loaded a Cobalt Strike Beacon payload, and the second loading Voldemort. These infection chains were initially triggered by distinct Microsoft Shortcut (LNK) files. 

UNK_FistBump RAR archive containing two distinct infection chains. 

Contents of job application zip containing two distinct infection chains. 

Infection chain 1: Cobalt Strike payload 

Execution of the first LNK file named 崗位匹配度說明.pdf.lnk runs a VBS script Store.vbs stored within the cache subfolder. This folder contains the following files: 

cache/Store.vbs  
cache/javaw.exe 
cache/崗位匹配度說明.pdf 
cache/rc4.log 
cache/jli.dll 

This Store.vbs script copies the files javaw.exe, jli.dll, and rc4.log to the C:UsersPublicVideos directory and opens a decoy document named 崗位匹配度說明.pdf (machine translation: Explanation of Job Compatibility.pdf). It then executes the benign signed executable javaw.exe, which is vulnerable to DLL-sideloading. This loads the malicious DLL jli.dll, which in turn decrypts the RC4-encrypted Cobalt Strike Beacon payload from the rc4.log file using the key qwxsfvdtv and loads it into memory. The Cobalt Strike Beacon payload uses a customized GoToMeeting malleable C2 profile and communicates with the Evoxt VPS C2 IP address 166.88.61[.]35 over port TCP 443. The jli.dll loader also establishes persistence by setting a HKEY_CURRENT_USERSOFTWAREMicrosoftWindowsCurrentVersionRun key value for runs to the path of the DLL sideloading executable javaw.exe. 

Infection chain 2: Voldemort payload 

Execution of the second LNK named 台灣大學-材料工程學類-薛豪.pdf.lnk runs another VBS file also called Store.vbs, this time within the MACOSX subfolder. This MACOSX folder contains the following files: 

_MACOSX/Store.vbs 
_MACOSX/台灣大學-材料工程學類-薛豪.pdf 
_MACOSX/CiscoSparkLauncher.dll 
_MACOSX/CiscoCollabHost.exe 
_MACOSX/Cisco.xml 

Similar to the Cobalt Strike infection chain, the Store.vbs script copies the malicious executable files to C:UsersPublicVideos and opens a different decoy document 台灣大學-材料工程學類-薛豪.pdf (Machine translation: National Taiwan University – Materials Engineering – Xue Hao.pdf). It then executes the benign signed executable CiscoCollabHost.exe, which is vulnerable to DLL sideloading and loads the malicious DLL CiscoSparkLauncher.dll. This DLL sideloading chain results in the delivery of the custom Voldemort backdoor, which uses Google Sheets for command and control (C2).  

UNK_FistBump resume decoy document. 

The specific Voldemort DLL sideloading infection chain and payload observed closely resembles one used by the China state-sponsored threat actor TA415 (APT41, Brass Typhoon), as previously documented by Proofpoint. An earlier Voldemort variation used by UNK_FistBump in May 2025 exfiltrated host information in plain text to the Google Sheets C2, while a later variation Base64-encoded and RC4-encrypted the values using the executable’s filename as the RC4 key (CiscoCollabHost.exe) in an identical manner previously highlighted in TA415 activity. 

Examining UNK_FistBump and TA415 attribution overlaps 

Voldemort is a custom malware family publicly reported by Proofpoint and Google that was historically only used by TA415 within Proofpoint telemetry. Proofpoint Threat Research also previously observed TA415 conducting spearphishing campaigns targeting the Taiwanese semiconductor sector using compromised Taiwanese university senders, in a similar manner to the highlighted UNK_FistBump activity.  

However, the observed UNK_FistBump campaigns diverge from activity typically tracked as TA415. For example, the Cobalt Strike infection chain uses a loader not typical of TA415, which usually favors ChaCha20-based loaders rather than the more simplistic RC4 loader used by UNK_FistBump. Similarly, the use of a hardcoded IP address for a C2, rather than a Cloudflare Worker or actor-controlled domain behind Cloudflare CDN, is atypical of TA415 activity. Due to these and other divergences, coupled with the wider propensity of custom capability sharing across Chinese cyberespionage threat actors, Proofpoint is tracking UNK_FistBump activity as distinct to TA415 at this time.  

UNK_DropPitch pitches semiconductor investment analysts 

In April and May 2025, Proofpoint observed another China-aligned threat actor tracked as UNK_DropPitch conducting targeted phishing campaigns against multiple large investment banks. This activity focused specifically on individuals specializing in financial investment analysis of Taiwanese semiconductor and technology sectors. The phishing emails were sent from attacker-owned email addresses and purported to come from a fictitious financial investment firm seeking to collaborate with the individual.  

Delivery 

Example UNK_DropPitch investment research collaboration phishing email (machine translated from Traditional Chinese). 

In a campaign observed in late April 2025, an UNK_DropPitch phishing email contained a link to hxxps://api[.]moctw[.]info/Intro.pdf. This resulted in the download of a file named Intro.zip containing both a benign executable vulnerable to DLL-sideloading and a malicious DLL libcef.dll, which are designed to load a simple custom backdoor Proofpoint tracks as HealthKick.  

UNK_DropPitch Intro.zip contents. 

Upon execution, both files are copied to a randomly named subfolder under the ProgramData directory and the following scheduled task named SystemHealthMonitor is created to execute [PDF] Introduction Documents 2 – 250409.exe every five minutes: 

schtasks.exe /Create /TN “SystemHealthMonitor” /TR “”C:ProgramDatazumArSAB[PDF] Introduction Documents 2 – 250409.Exe” -run” /SC MINUTE /MO 5 /F

The HealthKick backdoor then attempts to create a web socket to the actor-controlled IP address 82.118.16[.]72 over TCP port 465. HealthKick employs a FakeTLS protocol and expects a response from the C2 starting with the magic bytes 0x17 0x03 0x03 (the standard header for TLSv1.2), followed by the payload size. Due to the way the malware verifies that incoming packets start with these magic bytes and then later verifies this again, the FakeTLS header needs to be included twice for commands to be properly parsed and decoded, it is unclear if this was an intended feature or a mistake. This double FakeTLS header is then followed by a payload which is XOR encoded with the key mysecretkey. 

HealthKick TCP socket C2 communication. 

HealthKick is a simple backdoor that executes commands and captures their output via a redirected anonymous pipe, which is then sent back to the C2 using the same FakeTLS and XOR-encoded payload format. 

A later UNK_DropPitch campaign in late May 2025 linked to the Netlify URL   https://brilliant-bubblegum-137cfe[.]netlify[.]app/files/Introduction%20Document.zip

and again delivered a ZIP file containing an executable used to load a malicious DLL named pbvm90.dll. In this case, the resultant malware is a simple raw TCP reverse shell that communicates with the actor-controlled VPS server 45.141.139[.]222 again over TCP port 465 and persists via an identical scheduled task to the one noted above.  

This reverse shell features minimal exception or error handling, meaning the server’s response to the malware client connecting (“Server ready”) is interpreted as a command by the implant. Similarly, the reverse shell sends regular “ping” messages to its C2 as a heartbeat. Similar “ping” check ins were also received back from the C2 and often concatenated with the operator’s commands, resulting in errors. Proofpoint also observed typos in the command responses from the operators, indicating the commands are likely issued manually rather than in an automated fashion. 

UNK_DropPitch reverse shell errors and typos. 

Proofpoint observed UNK_DropPitch using this reverse shell to conduct initial enumeration and discovery against targets. Subsequently, if the target is deemed of interest, the group dropped the Remote Monitoring and Management (RMM) tool Intel Endpoint Management Assistant (EMA), which was configured to communicate with the actor-controlled domain ema.moctw[.]info. 

UNK_DropPitch infection chain. 

UNK_DropPitch network infrastructure analysis   

Both the 82.118.16[.]72 HealthKick backdoor C2 IP address and 80.85.156[.]234 Intel EMA C2 server used very similar reverse DNS names associated with the Russian VPS hosting provider ProfitServer and referenced the Mr. Robot character Elliot Alderson: 

elliot-alderson-971.pserver[.]space 
elliot-alderson-97.pserver[.]space 

Multiple similarly named email addresses have also been used by the threat actor. Pivoting on this artifact uncovered additional likely actor-controlled servers, several of which were used as C2 servers in subsequent June 2025 UNK_DropPitch campaigns targeting US academic and think tank organizations: 

31.192.234[.]97 (elliot-alderson-15.pserver[.]space) 
80.85.154[.]48 (elliot-alderson-973.pserver[.]space) 
80.85.154[.]101 (elliot-alderson-151.pserver[.]space) 
80.85.156[.]237 (elliot-alderson-974.pserver[.]space) 
80.85.157[.]116 (elliot-alderson-972.pserver[.]space) 
80.85.157[.]145 (elliot-alderson-978.pserver[.]space) 
82.118.16[.]72 (elliot-alderson-971.pserver[.]space) 
82.118.16[.]106 (elliot-alderson-972.pserver[.]space) 

Two of these servers were concurrently configured as SoftEther VPN servers, an open-source VPN product commonly used by a range of China-aligned threat actors for both infrastructure administration and tunnelling traffic out of victim networks. The hosting IP address for the UNK_DropPitch subdomain mx.moctw[.]info (43.247.132[.]96) was also configured as a SoftEther VPN server during time of use.  

The 80.85.154[.]101 IP address identified above concurrently exhibited a TLS certificate with the common name CN=AS.website (SHA256 fingerprint: 000062e9e212231328b660f759f8878ac47604b9609f71c05ad19d7ef56b17a8) on port TCP 4444. This certificate has been historically associated exhibited on C2 infrastructure associated with multiple custom malware families used by Chinese state-sponsored threat actors, most frequently the SideWalk (aka ScrambleCross) backdoor. The TLS certificate was also noted in Kaspersky reporting on the MoonBounce firmware rootkit and PWC reporting on TA415 (APT41, Brass Typhoon) activity, both in relation to SideWalk usage. At this time, Proofpoint analysts were unable to determine conclusively if the reuse of this TLS certificate is an artifact of a specific custom malware family shared across multiple China-aligned threat actors, most likely SideWalk, or of shared infrastructure provisioning across these groups. 

Additional China-aligned threat actors targeting Taiwanese semiconductor industry 

In addition to the highlighted UNK_FistBump and UNK_DropPitch activity, Proofpoint has also identified multiple additional Chinese state-sponsored threat actors specifically targeting organizations within Taiwan’s semiconductor industry. 

In March 2025, a China-aligned threat actor Proofpoint tracks as UNK_SparkyCarp conducted a credential phishing campaign using a custom adversary-in-the-middle (AITM) framework targeting a Taiwanese semiconductor industry company, which the group also previously targeted in November 2024. The phishing emails masqueraded as account login security warnings and contained a link to the actor-controlled credential phishing domain accshieldportal[.]com, as well as a tracking beacon URL for acesportal[.]com. 

Typical UNK_SparkyCarp AITM phishing kit landing page. 

Similarly, in October 2024 Proofpoint observed the China aligned threat actor UNK_ColtCentury (overlaps TAG-100, Storm-2077) sending benign conversation starter emails to legal personnel at a Taiwanese semiconductor organization in an attempt to engage the target. Based on related activity associated with this threat actor, this was likely an attempt to deploy the SparkRAT backdoor.  

Conclusion 

Within Proofpoint telemetry in recent years, traditional espionage targets – including governments, aerospace and defense companies, and non-governmental organizations – have continued to be consistently targeted by China-aligned espionage threat actors. Despite public reporting on semiconductor targeting from China-aligned threat actors, Proofpoint directly observed only sporadic targeting of this sector. Since March 2025, this shifted to sightings of multiple campaigns from different China-aligned groups specifically targeting this sector, with a particular emphasis on Taiwanese entities. 

As many well-established China-aligned threat actors have shifted tactics, techniques and procedures (TTPs) towards exploitation of edge devices and other initial access vectors, Proofpoint has observed an influx of new China-aligned clusters to the phishing threat landscape, as demonstrated by the subset of activity highlighted within this report. These emerging threat actors continue to exhibit long-standing targeting patterns consistent with Chinese state interests, as well as TTPs and custom capabilities historically associated with China-aligned cyberespionage operations. 

Indicators of compromise 

UNK_FistBump Network Indicators 

Indicator 

Type 

Description 

First Seen 

166.88.61[.]35 

IP address 

Cobalt Strike C2 

May 2025 

hxxps://sheets[.]googleapis[.]com:443/v4/spreadsheets/1z8ykHVYh9DF-b_BFDA9c4Q2ojfrgl-fq1v797Y5576Y 

URL 

Voldemort Google Sheets C2 

May 2025 

hxxps://sheets[.]googleapis[.]com:443/v4/spreadsheets/14H0Gm6xgc2p3gpIB5saDyzSDqpVMKGBKIdkVGh2y1bo 

URL 

Voldemort Google Sheets C2 

June 2025 

john.doe89e@gmail[.]com 

Email 

Malware delivery 

May 2025 

hxxps://3008[.]filemail[.]com/api/file/get?filekey=DeHjMusPPgDt5EsWxOcgYCfRh5yI6MIIg7vvwn9yFEzh93Cts5UxrfXMYEPiMWffVCp36UCsVgYSlC47WGdjHZ7m9bAw0QWcgqQZcg&pk_vid=007318ac7ca53d8717482475404ed5a2 

Delivery 

Filemail staging URL 

May 2025 

UNK_FistBump Malware Indicators 

1a2530010ecb11f0ce562c0db0380416a10106e924335258ccbba0071a19c852 

SHA256 

協助確認.rar 

June 2025 

084b92365a25e6cd5fc43efe522e5678a2f1e307bf69dd9a61eb37f81f304cc6 

SHA256 

台灣大學-材料工程學類-薛豪.rar 

June 2025 

85e4809e80e20d9a532267b22d7f898009e74ed0dbf7093bfa9a8d2d5403f3f9 

SHA256 

台灣大學-材料工程學類-薛豪.zip 

May 2025 

338f072cc1e08f1ed094d88aa398472e3f04a8841be2ff70f1c7a2e4476d8ef7 

SHA256 

台灣大學-材料工程學類-薛豪.rar 

May 2025 

13fad7c6d0accb9e0211a7b26849cf96c333cf6dfa21b40b65a7582b79110e4b 

SHA256 

崗位匹配度說明.pdf.lnk 

May 2025 

d783c40c0e15b73b62f28d611f7990793b7e5ba2436e203000a22161e0a00d0e 

SHA256 

台灣大學-材料工程學類-薛豪.pdf.lnk 

May 2025 

1016ba708fb21385b12183b3430b64df10a8a1af8355b27dd523d99ca878ffbb 

SHA256 

台灣大學-材料工程學類-薛豪.pdf.lnk 

May 2025 

13fad7c6d0accb9e0211a7b26849cf96c333cf6dfa21b40b65a7582b79110e4b 

SHA256 

Bumping工程師-台灣大學-材料工程學類-薛豪.pdf.lnk 

 

台灣大學-材料工程學類-薛豪.pdf.lnk 

May 2025 

1016ba708fb21385b12183b3430b64df10a8a1af8355b27dd523d99ca878ffbb 

SHA256 

2025年度薪資調整辦法公告.pdf.lnk 

June 2025 

bab8618bc6fc3fdfa7870b5fe0f52b570fabf0243d066f410a7e76ebeed0088c 

SHA256 

Store.vbs 

May 2025 

0d992762c69d624a1f14a8a230f8a7d36d190b49e787fd146e9010e943c5ef78 

SHA256 

Store.vbs 

May 2025 

ec5fef700d1ed06285af1f2d01fa3db5ea924de3c2da2f0e6b7a534f69d8409c 

SHA256 

Store.vbs 

June 2025 

82ecfe0ada6f7c0cea78bca2e8234241f1a1b8670b5b970df5e2ee255c3a56ef 

SHA256 

CiscoSparkLauncher.dll (Voldemort loader DLL) 

May 2025 

cd009ea4c682b61963210cee16ed663eee20c91dd56483d456e03726e09c89a7 

SHA256 

CiscoSparkLauncher.dll (Voldemort loader DLL) 

June 2025 

bbdad59db64c48f0a9eb3e8f2600314b0e3ebd200e72fa96bf5a84dd29d64ac5 

SHA256 

jli.dll (Cobalt Strike loader DLL) 

May 2025 

fc8f7185a90af4bf44332e85872aa7c190949e3ec70055a38af57690b6604e3c 

SHA256 

rc4.log (Cobalt Strike Beacon encrypted payload) 

May 2025 

 

UNK_DropPitch Network Indicators 

Indicator 

Type 

Description 

First Seen 

amelia_w_chavez@proton[.]me 

Email 

Malware delivery 

April 2025 

lisan_0818@outlook[.]com 

Email 

Malware delivery 

May 2025 

moctw[.]info 

Domain 

Malware delivery 

April 2025 

hxxps://api[.]moctw[.]info/Intro.pdf 

URL 

Malware delivery 

April 2025 

hxxps://api[.]moctw[.]info/Document-2025.4.25.pdf 

URL 

Malware delivery 

April 2025 

hxxps://api[.]moctw[.]info/Install.zip 

URL 

Malware delivery 

April 2025 

hxxps://brilliant-bubblegum-137cfe[.]netlify[.]app/files/Introduction%20Document.zip 

URL 

Malware delivery 

May 2025 

ema.moctw[.]info 

Domain 

C2 

April 2025 

www.twmoc[.]info 

Domain 

C2 

June 2025 

80.85.156[.]234 

IP Address 

C2 

April 2025 

82.118.16[.]72 

IP Address 

C2 

April 2025 

45.141.139[.]222 

IP Address 

C2 

May 2025 

80.85.156[.]237 

IP Address 

C2 

June 2025 

80.85.154[.]48 

IP Address 

C2 

June 2025 

UNK_DropPitch Malware Indicators 

7bffd21315e324ef7d6c4401d1bf955817370b65ae57736b20ced2c5c08b9814 

SHA256 

Intro.zip 

April 2025 

9b2cbcf2e0124d79130c4049f7b502246510ab681a3a84224b78613ef322bc79 

SHA256 

libcef.dll 

April 2025 

4ee77f1261bb3ad1d9d7114474a8809929f4a0e7f9672b19048e1b6ac7acb15c 

SHA256 

libcef.dll 

April 2025 

d3a71c6b7f4be856e0cd66b7c67ca0c8eef250bc737a648032d9d67c2c37d911 

SHA256 

[PDF] Introduction Document-2025.4.25.lnk 

April 2025 

366d7de8a941daa6a303dc3e39af60b2ffacaa61d5c1fb84dd1595a636439737 

SHA256 

Introduction Document.zip 

May 2025 

d51c195b698c411353b10d5b1795cbc06040b663318e220a2d121727c0bb4e43 

SHA256 

[PDF]Taiwan-Cooperation-Introduction-Document-20250521.exe 

May 2025 

ffd69146c5b02305ac74c514cab28d5211a473a6c28d7366732fdc4797425288 

SHA256 

pbvm90.dll 

May 2025 

 

UNK_SparkyCarp Network Indicators 

accshieldportal[.]com 

Domain 

UNK_SparkyCarp credential phishing domain 

March 2025 

acesportal[.]com 

Domain 

Tracking pixel domain 

March 2025 

hxxps://ttot.accshieldportal[.]com/v3/ls/click/?c=b5c64761 

URL  

Credential phishing URL 

March 2025 

hxxps://aqrm.accshieldportal[.]com/v2/account/validate/?vid=35f46f46 

URL 

Credential phishing URL 

March 2025 

hxxps://acesportal[.]com/T/bfzWhb 

URL 

Tracking pixel URL 

March 2025  

hxxps://acesportal[.]com/T/KRfzAH 

URL 

Tracking pixel URL 

March 2025 

menglunwuluegg226@proton[.]me 

Email  

Malware delivery 

March 2025 

lonelyboymaoxcz231@proton[.]me 

Email  

Malware delivery 

March 2025 

 

ET rules 

 

2063450 – ET HUNTING GoogleSheets API V4 Activity (Fetch Single Cell with A1 Notation) 

2063451 – ET HUNTING GoogleSheets API V4 Response (Single Cell with UUID) 

2063452 – ET HUNTING GoogleSheets API V4 Activity (Possible Exfil) 

2063453 – ET MALWARE Voldemort System Info Exfil 

2063454 – ET PHISHING Observed DNS Query to UNK_SparkyCarp Domain 

2063455 – ET PHISHING Observed DNS Query to UNK_SparkyCarp Domain 

2063456 – ET PHISHING Observed UNK_SparkyCarp Domain in TLS SNI 

2063457 – ET MALWARE Observed DNS Query to UNK_DropPitch Domain 

2063458 – ET MALWARE Observed UNK_DropPitch Domain in TLS SNI 

2063459 – ET PHISHING Observed UNK_SparkyCarp Domain in TLS SNI 

2063460 – ET MALWARE Observed DNS Query to UNK_DropPitch Domain 

2063461 – ET MALWARE Observed UNK_DropPitch Domain in TLS SNI Proofpoint Threat InsightRead More