Malicious
This file is confirmed confirmed malware — abuse.ch researchers uploaded this exact sample to MalwareBazaar as known malware. Delete it and scan your system.
0a49dc0d2ce725af34…332a5511e9The reasoning behind this verdict
The MT AI Engine weighs every signal from this scan — antivirus detections, sandbox behaviour, code signing, prevalence and historical matches — to reach a single, evidence-based verdict.
This file is confirmed confirmed malware — abuse.ch researchers uploaded this exact sample to MalwareBazaar as known malware. Delete it and scan your system. MalwareBazaar is a researcher-curated malware repository; hits there are ground-truth positives.
Each signal cites a concrete token from the evidence the arbiter saw — engine name, MITRE technique, signer string, or an exact count.
MalwareBazaar: confirmed malware
(no named signature)
First catalogued: 2024-01-23 20:27:33
- MalwareBazaar confirmed family: confirmed malware
- Researcher-uploaded malware sample
Delete this file and run a full-system antivirus scan.
What this file does
What it attempted when executed in an isolated sandbox
High concern: Hides inside another running program to evade antivirus.
High concern: Records what you type — keylogger behaviour.
High concern: Talks to a remote server to take commands or send out your data.
High concern: Sets itself to run automatically every time you start your PC.
High concern: Tries to disable or bypass your security software.
High concern: Hijacks how Windows loads programs so it runs automatically.
Moderate concern: Lists running programs — often to find security tools.
Translated from the file's technical behaviour during analysis. It never ran on your device.
Threat context
How trojans work
A trojan disguises itself as something useful or harmless to trick you into running it. Once open, it does its real job in the background — anything from stealing data to opening a back door or downloading more malware.
Bottom line:The disguise is the whole trick, so a trustworthy-looking name or icon means nothing.
What to do now
This file is dangerous. Treat it as harmful and remove it.
Don't open or run this file. Delete it from your Downloads (or wherever you saved it), then empty the Recycle Bin.
If you already opened it, disconnect from the internet and run a full scan with your antivirus — Windows Security, built into Windows, is sufficient.
From a different, clean device, change the passwords on your important accounts (email and banking first) and turn on two-factor authentication.
In future, only download software from the official website or an official app store.
FreddyBearDropper corroborated by 2 sources
- 3 YARA rulesFreddyBearDropper, golang_bin_JCorn_CSC846, yara_template
- MT AI Engineconfirmed malware
1 contradiction resolved by the scoring engine
What this file did when executed
This file was detonated in 1 sandbox and its runtime behaviour was observed.
Adversary techniques mapped to the MITRE ATT&CK framework.
- a83f:8110:0:0:0:0:0:2040
- a83f:8110:4747:47ff:4747:47ff:4747:47ff
- 13.107.39.203
- a83f:8110:0:0:1b00:100:2800:0
- a83f:8110:0:0:678c:21:0:0
- 13.107.4.50
- a83f:8110:2e67:6961:7473:0:206b:100
- a83f:8110:3000:2600:3000:0:5200:4f00
- 20.80.129.13
- a83f:8110:584a:b5b1:17cb:1ec8:0:0
- http://www.microsoft.com/pki/certs/MicrosoftTimeStampPCA.crt
- http://crt.sectigo.com/SectigoPublicCodeSigningCAR36.crt
- http://crt.sectigo.com/SectigoPublicCodeSigningRootR46.p7c
- http://www.microsoft.com/pki/certs/MicCodSigPCA_08-31-2010.crt
- \Device\Http\Communication
- C:\Users\<USER>\AppData\Local\Microsoft\Windows\PowerShell\StartupProfileData-NonInteractive
- C:\Users\<USER>\AppData\Local\Temp\~DFB930786F648561E5.TMP
- C:\Users\<USER>\AppData\Local\Microsoft\CLR_v4.0\UsageLogs\PowerShell.exe.log
- C:\Windows\ServiceProfiles\LocalService\AppData\Local\FontCache\Fonts\Download-1.tmp
- %USERPROFILE%\AppData\Local\Temp\__PSScriptPolicyTest_uiqdyllr.auh.ps1
- %USERPROFILE%\AppData\Local\Temp\__PSScriptPolicyTest_3eu4yjsc.yf0.psm1
- %USERPROFILE%\AppData\Local\Temp\__PSScriptPolicyTest_hs1iispu.3n3.ps1
- %USERPROFILE%\AppData\Local\Temp\__PSScriptPolicyTest_fw4su51u.oaa.psm1
- %USERPROFILE%\AppData\Local\Temp\__PSScriptPolicyTest_y10f1530.lel.ps1
- RasPbFile
- Global\3a886eb8-fe40-4d0a-b78b-9e0bcb683fb7
- CTF.LBES.MutexDefaultS-1-5-21-1482476501-1645522239-1417001333-500
- CTF.Compart.MutexDefaultS-1-5-21-1482476501-1645522239-1417001333-500
- CTF.Asm.MutexDefaultS-1-5-21-1482476501-1645522239-1417001333-500
Files this sample writes at runtime
This file drops 10 children at runtime. None are currently flagged malicious in our cache.
- 96ad1146eb96877eab59…87dcf7Never scannednever seen before
- d79ee7dc43e4a7157c1a…bd2cc4Never scannednever seen before
- 59658c85c438e04670c6…d0e48aNever scannednever seen before
- 982777c5b8a9a4301532…93e21eNever scannednever seen before
- 4553c61699dc9516219f…51b3b8Never scannednever seen before
- efb93c2f7b231b725a2c…bf1e66Never scannednever seen before
- 6ac2e776b309951afe3b…6d0837Never scannednever seen before
- 2181e905496bebc5a840…0d8359Never scannednever seen before
- 92dc1676d84e90c877f5…0fec9fNever scannednever seen before
- fca7e0397a5f8eee3f2e…f71279Never scannednever seen before
3 corroborating signals from researcher-curated sources
- FreddyBearDropperby Dwarozh HoshiarFreddy Bear Dropper is dropping a malware through base63 encoded powershell scrip.
- golang_bin_JCorn_CSC846by Justin CornwellCSC-846 Golang detection ruleset
- yara_template
YARA & heuristic rule matches
A researcher-curated or high-severity heuristic rule matched this sample. These rules target specific malware families and are near-definitive.
- FreddyBearDropper
- golang_bin_JCorn_CSC846
- yara_template
MITRE T1055 (Process Injection) observed — CreateRemoteThread / APC / reflective-DLL injection. The payload is being smuggled into a legitimate process to bypass AV hooks.
EvidenceC:\Windows\System32\svchost.exe -k NetworkService -pSandbox observed process activity targeting LSASS (Windows credential store). Legitimate software has no business reading LSASS memory — this is Mimikatz-shape behaviour.
EvidenceC:\Windows\system32\lsass.exeSample contacted 18 external IP address(es) and zero domains. Benign software virtually always uses DNS; no-DNS direct-IP C2 is a strong malware indicator because it bypasses reputation systems and dodges domain-based blocklists.
Evidencea83f:8110:0:0:0:0:0:2040 · a83f:8110:4747:47ff:4747:47ff:4747:47ff · 13.107.39.203
1 detection across 75 engines
Section entropy & packers
Section-level entropy and packer detection from the PE header. Nothing suspicious here — entropy is within the normal range for unpacked code.
How widely this file has been seen
Widely seen in the wild for a long time. High prior this is legitimate; isolated detections on common-old files are usually false positives.
Forensic fingerprint
- File name
- TCPOptimizer.exe
- Size
- 668.0 KB
- MIME type
- (unknown)
- Detected type
- Win32 EXE
- SHA-256
- 0a49dc0d2ce725af347df632539b70afcfd22b38e285920b515143332a5511e9
- MD5
- d8292150c8ce862a97a923318df07805
- SHA-1
- 917f917ff9fe33e199388e5e1d4c0696882d2991
- PE imphash
- 6cce23cb7f6c7d69f3ef22e1fb2d232f
- First seen (VT)
- 1/9/2021, 4:29:59 PM
- Last analysis (VT)
- 6/29/2026, 11:40:55 PM
- First scan (MalwareTips)
- 4/20/2026, 3:48:38 PM
- Last scan (MalwareTips)
- 6/30/2026, 5:43:07 AM
- Community reputation
- +126trusted
Safety FAQ
Common questions about TCPOptimizer.exe, answered from the scan data above.
- Yes — TCPOptimizer.exe is malicious, so do not run it, and delete it. 1 of 75 antivirus engines flag it (family: confirmed malware). It behaves as a trojan — malware disguised as something harmless to trick you into running it. It's also a confirmed malware sample catalogued by the abuse.ch threat-intelligence community. If you've already run it, see the removal and recovery steps below.
- TCPOptimizer.exe is a Windows executable program, about 668 KB. Our analysis identifies it as malicious (family: confirmed malware) — a trojan — malware disguised as something harmless to trick you into running it. Because a file's name and icon can be faked, the safest way to identify it is by its cryptographic hash (below), not its filename.
- 1 of 75 antivirus engines flagged TCPOptimizer.exe, 1 of them as outright malicious. A detection rate at this level is a reliable signal that the file is dangerous.
- Act quickly. 1) Disconnect the device from the internet to stop the malware communicating or spreading. 2) Run a full scan with reputable anti-malware software (such as Malwarebytes) and quarantine everything it finds. 3) Change your important passwords from a DIFFERENT, clean device — many threats log keystrokes or steal saved credentials. 4) If you bank or shop on this device, watch closely for fraud and alert your bank. 5) For a confirmed infection, the most reliable fix is to back up your personal files and reinstall the operating system for a clean start.
- To remove TCPOptimizer.exe: 1) restart into Safe Mode (Safe Mode with Networking if you need to download a tool) so the malware doesn't auto-start. 2) Run a full scan with reputable anti-malware software and let it quarantine or delete the detections. 3) Delete the original TCPOptimizer.exe file and empty the Recycle Bin/Trash. 4) Check your browser extensions, startup items, and scheduled tasks for anything unfamiliar. 5) Reboot and scan again to confirm it's gone. If detections keep coming back, a clean operating-system reinstall is the most dependable cure.
- TCPOptimizer.exe is classified as a trojan — malware disguised as something harmless to trick you into running it. Engines attribute it to the confirmed malware family. Knowing the family matters because it tells you the likely impact — data theft, remote control, file encryption, or unwanted ads — and guides the cleanup.
- Yes — this exact file is a known, catalogued malware sample in the abuse.ch MalwareBazaar threat-intelligence feed, first seen on January 23, 2024. A confirmed listing there is strong, independent evidence that the file is malicious.
- The SHA-256 hash of TCPOptimizer.exe is 0a49dc0d2ce725af347df632539b70afcfd22b38e285920b515143332a5511e9, and its MD5 is d8292150c8ce862a97a923318df07805. This hash is the file's unique fingerprint — two files with the same SHA-256 are identical. Use it to confirm you're looking at exactly this file (not just one with the same name) when comparing against antivirus databases or a download's published checksum.
- This report reflects the scan run on April 20, 2026. Because a file's hash never changes, the identity of TCPOptimizer.exe is fixed — but antivirus coverage improves over time, so a file that looks clean today can pick up detections later (and vice-versa). If you need the latest picture, MalwareTips staff can re-run the analysis from scratch.
Reviews & malware reports(0)
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