Malicious PDF — malware analysis report

Static analysis result for SHA-256 a4a91cb23894a3af…

MALICIOUS

PDF

76.2 KB Created: 2021-03-14 08:02:17 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2026-06-04
MD5: a870255a784e8a6cb09bac6375a81f9a SHA-1: 37d4630915c36bc86b8661a31a2082c23e138b3d SHA-256: a4a91cb23894a3af7d132ef4ad119cfd39599e7b4aaa2a7558279358bab943d8
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF file is identified as malicious by ML classifiers and ClamAV, indicating it's a phishing or trojan delivery mechanism. It contains numerous external URIs, with a primary suspicious URL being https://mezovuduw.ru/wix?keyword=traffic+signs+worksheet+pdf, suggesting a lure to a malicious site. The document body, though heavily obfuscated, hints at a 'traffic signs worksheet pdf' theme, likely a pretext for the malicious activity.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL https://mezovuduw.ru/wix?keyword=traffic+signs+worksheet+pdf PDF link annotation
    • https://bupulaserora.weebly.com/uploads/1/3/1/4/131437689/3913913.pdfIn PDF document text
    • http://dietnatur.fun/659465256073uxwk.pdfIn PDF document text
    • https://s3.amazonaws.com/dusined/refractory_heart_failure_guidelines.pdfIn PDF document text
    • https://mogasijukunuv.weebly.com/uploads/1/3/4/0/134042787/7936667.pdfIn PDF document text
    • http://netewe9.xyz/22101309008sbndg.pdfIn PDF document text
    • https://guvoruba.weebly.com/uploads/1/3/4/7/134742814/7572778.pdfIn PDF document text
    • http://intekzafast.online/which_english_accent_is_easy_to_learnpsh43.pdfIn PDF document text
    • https://s3.amazonaws.com/wizomoravazub/51929202709.pdfIn PDF document text
    • https://s3.amazonaws.com/vuliwisuwig/zazam.pdfIn PDF document text
    • https://bomejafir.weebly.com/uploads/1/3/4/7/134725936/9193036.pdfIn PDF document text
    • http://xonubevobupok.iblogger.org/free_music_player_for_windows_10.pdfIn PDF document text
    • https://pumutetigowon.weebly.com/uploads/1/3/4/6/134699291/374937.pdfIn PDF document text
    • http://zijogeminevuxa.iblogger.org/jang_ye_won_reporter.pdfIn PDF document text
    • http://mezoterilijixa.22web.org/windows_10_enterprise_ltsb_1709.pdfIn PDF document text
    • https://s3.amazonaws.com/dibedamoka/adobe_reader_free_file_hippo.pdfIn PDF document text
    • https://s3.amazonaws.com/degisapemifa/takaxogomajofidupudosame.pdfIn PDF document text
    • http://nout-prokat.website/laraz9p9rv.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://ec2d952e-5494-46d8-b841-fee222248b17.filesusr.com/ugd/9713d5_4aede849464a4f7e92b931516cb475c8.pdf?index=trueIn PDF document text
    • http://wedizakur.epizy.com/75590934692.pdfIn PDF document text
    • https://d89a15f7-21b5-45f0-b9b4-bc5b7be68842.filesusr.com/ugd/18e821_80540ad21ba64211a06024a812453873.pdf?index=trueIn PDF document text
    • http://sufumawug.epizy.com/96461992032.pdfIn PDF document text
    • https://44407f20-7244-4107-9544-84d8151b6f9a.filesusr.com/ugd/8508de_24684a72456845d2b9999162de0c80c2.pdf?index=trueIn PDF document text
    • http://paruwegugu.rf.gd/pulenibadapame.pdfIn PDF document text
    • https://28932ed2-21d9-4123-99cb-fcff0aac4472.filesusr.com/ugd/cc089a_ecad729d778b41c78ec607d1f0458ec1.pdf?index=trueIn PDF document text
    • http://vuzudaru.epizy.com/what_is_the_normal_heart_rate_of_daphnia.pdfIn PDF document text
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ed59.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED59 5488 bytes
SHA-256: 04688aa26f41fbca49d94fcd8863eacb02e5f057d221da90fd491ef230720e84
font_01_sfnt_off00010016.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10016 10220 bytes
SHA-256: a092647dc444741587b57d2d0908adbfe403a347afd84415820ac8aac56cecff