GridinSoft Threat Intelligence
zlib1.dll file report
Why it matters
Evidence available for this file
No final classification is available yet.
First seen 2021-01-14 13:54:38 (5 years ago); latest analysis 2021-01-14 13:54:38 (5 years ago).
Signed by Blue Century Software Co., Ltd. The signature is reported as valid, but signed files can still be bundled or abused.
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
- Use the hash and metadata below to verify the exact file identity.
- Review publisher, signature, paths, and PE details for inconsistencies.
- 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 reported company name is Zlib. The current detection status is Undefined, based on the latest analysis from 2021-01-14 13:54:38 (5 years 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 |
| Company Name: | Zlib |
| MD5: | 56d5389fd5dddcdd3255336167b5683c |
| Size: | 88 KB |
| First Published: | 2021-01-14 13:54:38 (5 years ago) |
| Latest Published: | 2021-01-14 13:54:38 (5 years ago) |
| Status: | Undefined (on last analysis) | |
| Analysis Date: | 2021-01-14 13:54:38 (5 years ago) |
Overview
| Signed By: | Blue Century Software Co., Ltd |
| Status: | Valid |
The signature on zlib1.dll is reported as valid. A valid signature helps confirm publisher identity, but it does not automatically make the file safe if the installer was bundled, abused, or downloaded from an untrusted source.
Common Places:
| %programfiles% |
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 1 countries. Use this signal to compare local evidence with where the sample is most often reported.
The strongest geographic signal for this file is Italy with 100.0% of observed hits. Geographic distribution can help identify targeted campaigns, regional software bundles, or where a file is most commonly reported.
OS Version:
The most common operating system signal for zlib1.dll is Windows 10 with 100.0% 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.
PE Sections:
Section layout highlights raw-size concentration, repeated names, packer markers, and hashes that can be compared across related samples.
fb3eaf5f44062b7d42dbd85cc675d83e
bd7e579b89c755c8500d95e13eab3504
d41d8cd98f00b204e9800998ecf8427e
e26b95848ef2f8c86d11449797fd50e2
323b2c261624a2ea56fe3c3757a9653b
36ccbb297d53d3e054df3bafe19ed25b
9f7837634a6ec513794db623c0eadbe5
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.