Malicious PDF — malware analysis report

Static analysis result for SHA-256 aa5ff4aff57dadbe…

MALICIOUS

PDF

75.4 KB Created: 2021-09-14 21:13:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 94c475b7700fb27b91de9ad2a7cd3899 SHA-1: e420b7e7a45485a4d027b4618613c9550f38e84d SHA-256: aa5ff4aff57dadbe44b173141cf802baddd260ac256cddd4bb24c6ebf15070ca
146 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. The PDF contains numerous embedded URLs, many of which point to disposable hosting and appear to be part of a link farm. The heuristic 'SE_CALLBACK_LURE' suggests a callback phishing or tech-support scam context, indicating the document's content is designed to trick the user into interacting with a malicious link or phone number.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9980

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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 https://laborke.ru/uplcv?utm_term=atomic+number+and+atomic+radius PDF link annotation
    • http://sin-hua.org/userfiles/73607406348.pdfIn PDF document text
    • http://studiofagiani.eu/userfiles/files/gazexono.pdfIn PDF document text
    • https://monarchwinemerchants.com/wp-content/plugins/super-forms/uploads/php/files/7e8c6927548e63e293454757572c9be9/dajepafiguvisofizusezibab.pdfIn PDF document text
    • http://islaminkiel.de/webmisr/uploadwebmisr/file/bonudomisitogatipeginas.pdfIn PDF document text
    • https://yingzhaoliuart.com/upload/file/tupopasoz.pdfIn PDF document text
    • https://kaskad-74.ru/images/uploads/19069030997.pdfIn PDF document text
    • http://antonioruizabogados.es/userfiles/file/61269420048.pdfIn PDF document text
    • http://gpba.ge/admin/ckeditor/ckfinder/userfiles/files/zutarizivo.pdfIn PDF document text
    • http://decom.pro/admin/ckfinder/userfiles/files/pufopajuraruz.pdfIn PDF document text
    • https://sssmri.com/ckfinder/userfiles/files/48990024505.pdfIn PDF document text
    • http://congluc.com/upload/files/26688705608.pdfIn PDF document text
    • http://thoitranglani.com/upload/files/mujagebi.pdfIn PDF document text
    • https://812423.qqtogeljackpot2.com/contents/files/xukolatujirun.pdfIn PDF document text
    • https://sk-developers.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613c65a356b6a---bugusezaduboxibinelola.pdfIn PDF document text
    • https://wisestudentz.com/userfiles/file/joxunoxuzap.pdfIn PDF document text
    • http://greentreeprep.com/cote_dor_import/admin/ckfinder/userfiles/files/ledinojuxijowojufatafamin.pdfIn PDF document text
    • http://gniortho.com/files/Upload/file/21080819250.pdfIn PDF document text
    • http://coverybox.box8websites.com/ckfinder/userfiles/files/kedudutonevarulexipazize.pdfIn PDF document text
    • https://clubkdo.fr/img/pics/files/46408903601.pdfIn PDF document text
    • http://mobitransjogja.com/files/34142934662.pdfIn PDF document text
    • http://crediramasrl.it/public/file/4992796635.pdfIn PDF document text
    • http://smenergy.kr/uploaded/file/10182099586137fb68d0a94.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://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_off0000c4c1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC4C1 16636 bytes
SHA-256: d31eeb28d84b2bb0c0344aa88515e7a717b813437e52df870d07cf9c7d97fd12
font_01_sfnt_off0000ef42.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF42 10708 bytes
SHA-256: 081cae4a51df6641e5bdc045d135708d8518151272930077efae830639232f06
font_02_sfnt_off000107d5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x107D5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1