Malicious PDF — malware analysis report

Static analysis result for SHA-256 0c4e8167df6e1940…

MALICIOUS

PDF

83.0 KB Created: 2021-09-15 17:45:12 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 97f8c60a63da92ba90b1e0df9a701c8e SHA-1: c475162789f25850bc155fa56e574b3ca3e508bd SHA-256: 0c4e8167df6e194008e9fa7c831d8f3f443377700f09ed8c9f7f8364274cfd8a
146 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The presence of numerous embedded URLs pointing to PDFs, combined with heuristics flagging it as a link farm and a callback phishing lure, suggests it's used to distribute further malicious content or engage in phishing. No scripts were extracted, but the document structure and URL patterns are consistent with malware distribution or phishing campaigns.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 6

  • 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.
  • Callback phishing phone lure medium SE_CALLBACK_LURE
    Document asks the user to call a phone number in billing, refund, subscription, fraud, or security context — consistent with callback phishing or tech-support scam patterns. Suppressed for legitimate-issuer (IRS/gov/official-form) documents that carry no urgency or charge/dispute escalation.
  • 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 http://tcyy88.com/userfiles/file/2021091400111473499.pdf In PDF document text
    • http://ballmillfactory.com/d/files/kotaginaburogi.pdfIn PDF document text
    • http://haohanlegend.com/Uploadfiles/files/duwasadazowid.pdfIn PDF document text
    • http://www.elmundodelapiscina.com/ckfinder/userfiles/files/xifafuxuseze.pdfIn PDF document text
    • http://sirindhorn.net/upload/File/16694638085.pdfIn PDF document text
    • http://www.gieskestukadoors.nl/ckfinder/files/files/74397867096.pdfIn PDF document text
    • http://geo-equipe.it/userfiles/files/pifawedeziruninujinowu.pdfIn PDF document text
    • https://gyn-koe70.de/obrazky/file/wadusufunefudaporor.pdfIn PDF document text
    • https://www.karelo.com/uploads/File/penuwoxewejomaliw.pdfIn PDF document text
    • https://daulte.ch/ckfinder/userfiles/files/zudamujaruwuguxolisifu.pdfIn PDF document text
    • http://www.icf-plant.com/files/file/pojovitifano.pdfIn PDF document text
    • http://melvin.cz/data/26563740488.pdfIn PDF document text
    • https://alummaswaja.com/yii/sdbalikpapan/home/images/upload/files/6806946021.pdfIn PDF document text
    • http://tatooazh.ru/files/files/mixupisabo.pdfIn PDF document text
    • http://refpecsbelvaros.hu/kepek/files/16198076663.pdfIn PDF document text
    • http://tnslib.tools/userfiles/files/16871621333.pdfIn PDF document text
    • http://bluecars.pl/userfiles/file/webevikafiritepe.pdfIn PDF document text
    • http://fandimnarodaku.cz/upload/file/58542982113.pdfIn PDF document text
    • http://shethof.ch/cgi-bin/dynamisch/file/62362610095.pdfIn PDF document text
    • https://tranthachcaodanang.com/uploads/image/files/bilumi.pdfIn PDF document text
    • http://laulumaja.fi/ckfinder/userfiles/files/rukuwapulevukuvisuvir.pdfIn PDF document text
    • http://velkoobchod-man.eu/ckfinder/userfiles/files/77097242099.pdfIn PDF document text
    • https://condominiovillage.com/userfiles/file/foxavojid.pdfIn PDF document text
    • http://travelport.pl/userfiles/file/rijoxefoneronuzez.pdfIn PDF document text
    • https://www.bouwenaaneensterkwerkgeversmerk.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1614141c6906a4---raxikes.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3vuEKuznOb8/uplcv?utm_term=bully+anniversary+edition+free+download+for+androidPDF link annotation
    • 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://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000df63.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDF63 10768 bytes
SHA-256: 534d3ed4b6cd05c6f2da284daa190a8548388e253e7d265e89cd244508c8ef05
font_01_sfnt_off0000f861.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF861 17420 bytes
SHA-256: 6dc615b0565516aaad3970b95d02a02d748619bcc82f20e6789697285ae1c05c
font_02_sfnt_off000125c0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x125C0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1