Malicious PDF — malware analysis report

Static analysis result for SHA-256 52041c80aeed64f8…

MALICIOUS

PDF

95.8 KB Created: 2021-09-07 04:30:24 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: b8d6a998d42092b48b982bbc8be17a81 SHA-1: a0338b74808ca4c2f92c149ece872ca3e94b87b9 SHA-256: 52041c80aeed64f8a6fdd129ff87eef6efcb6a0c8dae0d2cb7b7c81b5ed601fb
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was detected as malicious by ML classifiers and ClamAV, indicating a phishing or trojan payload. The document body is heavily obfuscated, but heuristics indicate it functions as a link farm, directing users to potentially compromised WordPress upload storage and other disposable hosting sites. While no scripts were directly extracted, the presence of embedded URLs and the 'SE_INVOICE_LURE' heuristic suggest the document's purpose is to trick users into clicking malicious links, likely leading to further malware downloads or credential harvesting.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9965

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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.
  • Fake invoice / payment lure low SE_INVOICE_LURE
    Document contains invoice or payment language paired with an action verb — useful context when combined with link, macro, or attachment indicators
  • 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://kor-ra.ru/UserFiles/file/wutazaposunol.pdf In PDF document text
    • http://julieesteban.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d0702383b8c---befav.pdfIn PDF document text
    • http://lbhs1965.com/clients/6/6b/6bdd8f708684a1f547efbf97e1630fe5/File/4004219380.pdfIn PDF document text
    • https://solarconsulting.org/wp-content/plugins/super-forms/uploads/php/files/58435ebb662c02f1769929ee597ef450/dawativevavofet.pdfIn PDF document text
    • http://tottazo.com/userfiles/file/jomuxujesajofofuwaf.pdfIn PDF document text
    • https://casabresciani.it/uploads/file/77454399404.pdfIn PDF document text
    • http://chinahongji.com/d/files/pepesenujigu.pdfIn PDF document text
    • https://hgqq.hk/tony/churchofgod/ckfinder/userfiles/files/tesobedusexofa.pdfIn PDF document text
    • http://ekonopuntos.com/campannas/file/baginag.pdfIn PDF document text
    • http://kondicionery-lubertsy.ru/upload_picture/file/xejavulenuna.pdfIn PDF document text
    • http://mosjob.ru/images/file/53453051530.pdfIn PDF document text
    • http://szentdorottyapatika.hu/files/3473131628.pdfIn PDF document text
    • http://smartcookieacademy.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c0d54c074b0---wonirixi.pdfIn PDF document text
    • https://mariapolis.net/ckfinder/userfiles/files/6704711504.pdfIn PDF document text
    • http://chikatere.com/Upload/files/wozevagomugaxunira.pdfIn PDF document text
    • http://alompar.hu/uploads/content_files/files/galurujubaxosikuvi.pdfIn PDF document text
    • http://ggmtc.net/userfiles/files/pugodozuna.pdfIn PDF document text
    • http://maslag.eu/userfiles/file/43529818781.pdfIn PDF document text
    • http://7linc.com/uploadfiles/fckeditor/20210802/file/16278887638536.pdfIn PDF document text
    • https://nepalonetours.com/userfiles/files/97324443127.pdfIn PDF document text
    • http://ttlengenharia.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1608f6ead5c5fb---70551230469.pdfIn PDF document text
    • http://proia.bg/userfiles/file/fexodudagikowuju.pdfIn PDF document text
    • http://ziguratex.com/helpdesk/app/webroot/img/userfiles/files/fezigufizemawutinoxatos.pdfIn PDF document text
    • https://devcons.org/uploads/userfiles/files/baperadurifonurevuguto.pdfIn PDF document text
    • https://zemiigori.com/uploads/file/dubipokidupuzubab.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/Om9ozkHLxGw/uplcv?utm_term=article+1+of+the+constitution+worksheetPDF 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_off000114ca.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x114CA 17120 bytes
SHA-256: bfcbefc7c3c991127a066a722967a36ab3db350b0aa83fb4136b3cb351285e5a
font_01_sfnt_off000140fc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x140FC 10584 bytes
SHA-256: dd3a38e660b17fae7eaaea75007adf7565a5bf328d8fbbbee0cedb562c9f5919
font_02_sfnt_off0001593c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1593C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1