zlib1.dll file report
ThreatInfo file report
zlib1.dll
Why it matters
Evidence available for this file
No final classification is available yet.
First seen 2017-05-21 09:01:48 (8 years ago); latest analysis 2025-11-28 23:00:26 (6 months ago).
Product metadata: zlib.
Signed by TAOBAO (CHINA) 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 current detection status is Undefined, based on the latest analysis from 2025-11-28 23:00:26 (6 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: | 53a4f22e10c0aa5d092783425ece8652 |
| Size: | 64 KB |
| First Published: | 2017-05-21 09:01:48 (8 years ago) |
| Latest Published: | 2025-11-28 23:00:26 (6 months ago) |
| Status: | Undefined (on last analysis) | |
| Analysis Date: | 2025-11-28 23:00:26 (6 months ago) |
Overview
| Signed By: | TAOBAO (CHINA) 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:
| %localappdata%\ucbrowser\user data\thunder\1.0.0.0\download |
| %localappdata%\ucbrowser\user data_i18n\thunder\1.0.0.0\download |
| %programfiles%\ucbrowser\application\downloader\download |
| %programfiles%\ucbrowser\application\new\new_downloader\download |
| %programfiles%\ucbrowser\application\5.6.11651.1013\update\0\remote\0_beta_package\downloader\download |
| %programfiles%\ucbrowser\application\5.0.1104.0\update\0\remote\0_beta_package\downloader\download |
| %profile%\dministrator\local settings\application data\ucbrowser\user data\thunder\1.0.0.0\download |
| %profile%\dministrador\configuración local\datos de programa\ucbrowser\user data_i18n\thunder\1.0.0.0\download |
| %profile%\dministrator\local settings\application data\ucbrowser\user data_i18n\thunder\1.0.0.0\download |
| %programfiles%\ucbrowser\temp\source620_24331\chrome-bin\downloader\download |
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.
Geography:
| 15.6% | ||
| 8.9% | ||
| 8.6% | ||
| 6.7% | ||
| 5.5% | ||
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The strongest geographic signal for this file is Indonesia with 15.6% of observed hits. Geographic distribution can help identify targeted campaigns, regional software bundles, or where a file is most commonly reported.
OS Version:
| Windows 7 | 44.3% | |
| Windows 10 | 41.0% | |
| Windows 8.1 | 9.7% | |
| Windows 8 | 2.5% | |
| Windows XP | 1.8% | |
| Windows Vista | 0.4% | |
| Windows Server 2012 R2 | 0.3% | |
| Windows Embedded 8.1 | 0.1% |
The most common operating system signal for zlib1.dll is Windows 7 with 44.3% 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 systems. The subsystem is Windows GUI. PE header values are useful for triage, especially when they do not match the expected publisher, product, or release timeline.
| Subsystem: | Windows GUI |
| PE Type: | pe |
| OS Bitness: | 32 |
| Image Base: | 0x215b0000 |
| Entry Address: | 0x0000a18b |
PE Sections:
| Name | Size of data | MD5 |
| .text | 37888 | 44f04606ade7fab8b963523e65b4b80a |
| .rdata | 18432 | 96f60eb6585bf33256eae61585dd67fe |
| .data | 512 | 6d0d0434a6cfc60a410b3eb130facfe4 |
| .rsrc | 1024 | 0d55339e24844c14a0f7c80f1795621c |
| .reloc | 1024 | fc240a21f98683c5307fd34c842ea264 |
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.
More information:
