GridinSoft Threat Intelligence

zlib1.dll file report

Under review File reputation report
MD5 d90dad5eea33a178bac56fff2847d4c2
Latest seen 2025-06-16 23:01:19 (11 months ago)
First seen 2017-05-21 06:06:34 (9 years ago)
Size 98 KB
Product zlib

Why it matters

Evidence available for this file

Detection

No final classification is available yet.

Timeline

First seen 2017-05-21 06:06:34 (9 years ago); latest analysis 2025-06-16 23:01:19 (11 months ago).

Publisher context

Product metadata: zlib.

Observed locations

ThreatInfo has seen this file in user or system paths listed below. Unexpected locations increase the need for local verification.

Recommended action

What to do next

  1. Use the hash and metadata below to verify the exact file identity.
  2. Review publisher, signature, paths, and PE details for inconsistencies.
  3. Run a local scan if the file appears unexpectedly or starts with Windows.

File context

zlib1.dll is a Windows file recorded in the ThreatInfo database. It is associated with zlib. The current detection status is Undefined, based on the latest analysis from 2025-06-16 23:01:19 (11 months ago).

ThreatInfo does not have a final classification for this file yet. Use the technical details below to compare the hash, size, signature, and observed locations with the copy found on your device.

File Details

Product Name: zlib
MD5: d90dad5eea33a178bac56fff2847d4c2
Size: 98 KB
First Published: 2017-05-21 06:06:34 (9 years ago)
Latest Published: 2025-06-16 23:01:19 (11 months ago)
Status: Undefined (on last analysis)
Analysis Date: 2025-06-16 23:01:19 (11 months ago)

Common Places:

%programfiles%\tencent\qzone
%programfiles%\torrent search
%programfiles%\tencent\qzone\ver_253.413
%programfiles%\tencent\qzone\ver_247.311
%programfiles%\tencent\qzone\ver_247.312
%programfiles%\kmsnano\data
%programfiles%\tencent
%programfiles%
%windir%
%programfiles%\drivergenius\app

ThreatInfo has observed zlib1.dll in the locations listed above. Files found in temporary folders, user profile folders, startup locations, or unusual application directories should be reviewed more carefully than files installed under a known program directory.

Geographic signal

Observed country distribution

ThreatInfo has seen zlib1.dll across 44 countries. Use this signal to compare local evidence with where the sample is most often reported.

Top country Taiwan
Share 37.0%
Low High activity

The strongest geographic signal for this file is Taiwan with 37.0% of observed hits. Geographic distribution can help identify targeted campaigns, regional software bundles, or where a file is most commonly reported.

OS Version:

Windows 10 71.7%
Windows 7 20.8%
Windows 8.1 3.2%
Windows Server 2012 R2 1.1%
Windows Server 2008 R2 1.0%
Windows Server 2003 1.0%
Windows 8 0.8%
Windows XP 0.3%
Windows Server 2012 0.1%
Windows Server 2016 0.1%

The most common operating system signal for zlib1.dll is Windows 10 with 71.7% of observed hits. If your system differs from the common profile, check whether the file was introduced by a specific installer, archive, or removable device.

Analysis

zlib1.dll is identified as pe for 32-bit systems. The subsystem is Windows CUI. PE header values are useful for triage, especially when they do not match the expected publisher, product, or release timeline.

Format pe
Architecture 32-bit
Subsystem Windows CUI
Entry point 0x000010c0
Image base 0x62e80000

PE Sections:

Sections 9
Raw data 99328

Section layout highlights raw-size concentration, repeated names, packer markers, and hashes that can be compared across related samples.

.text 73216 bytes · 73.7% of section data
MD5 78d27b07fdf07ebc8196c826ebd1af58
.data 512 bytes · 0.5% of section data
MD5 2b112b63f3bf04085840c476628bdb91
.rdata 19456 bytes · 19.6% of section data
MD5 1ffa5c559b607b83a58a5ab783306dc8
.eh_fram 512 bytes · 0.5% of section data
Uncommon name
MD5 137a2057b00753c1c3b3c2108df747c4
.bss 0 bytes · 0.0% of section data
MD5 00000000000000000000000000000000
.edata 1536 bytes · 1.5% of section data
MD5 775321ae8af621ef316af51b376826f2
.idata 1536 bytes · 1.5% of section data
MD5 3c6af2b45ce13f543d61a0d6ecc89d09
.rsrc 1024 bytes · 1.0% of section data
MD5 5f9483adfbfdf4a582cb8e2ec11dc3a4
.reloc 1536 bytes · 1.5% of section data
MD5 20078379355891e12f3e2b191e95c78a

PE section names and hashes can reveal packing, injected resources, or unusual build artifacts. Sections with uncommon names, very large raw data, or hashes that differ from a trusted copy deserve additional review.

Report conclusion

This file is still under review

ThreatInfo has not assigned a final verdict yet. Compare the file hash, location, signature, and publisher before trusting the file on a production system.

Scan with GridinSoft Anti-Malware Use a local scan if the file origin or behavior is unclear. Check this hash on VirusTotal

Recommended next steps

  • Compare the local file MD5 with d90dad5eea33a178bac56fff2847d4c2.
  • Check the file path, publisher, and signature against the details in this report.
  • Run a GridinSoft scan if the source, path, or behavior looks unusual.