Malicious PDF — malware analysis report

Static analysis result for SHA-256 3906d8e8c9c2c3a2…

MALICIOUS

PDF

81.8 KB Created: 2021-09-11 13:41:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 936e0c0db7fa9e40a6d836c667eb38a5 SHA-1: 0bc792d7bc0b20d0842f53b8960bd0f67cfd3883 SHA-256: 3906d8e8c9c2c3a2fbe30b5bf6a7642c8964fa66588704242c0fa1570f70cf1b
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs, many of which point to potentially compromised websites or disposable hosting, characteristic of a link farm designed to redirect users. The presence of these links and the overall detection suggest an attempt to lure users to malicious sites, likely for phishing or further malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9968

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
  • 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.
  • 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://xingyeknitting.com/userfiles/files/56616218683.pdf In PDF document text
    • http://mtreurope.com/ckfinder/userfiles/files/luperipa.pdfIn PDF document text
    • http://asupuro.com/user_data/image/file/55827282104.pdfIn PDF document text
    • https://serrechevalier-skifun.com/imagesfile/dumosupusubelu.pdfIn PDF document text
    • https://radekslodkiewicz.pl/files/file/logawazebumuvusulemibedaf.pdfIn PDF document text
    • http://lncxjzxxw.com/upload_fck/file/2021-9-2/20210902013424730063.pdfIn PDF document text
    • http://prota.ru/upload/files/nilofudok.pdfIn PDF document text
    • http://dabien.co.kr/wp-content/plugins/formcraft/file-upload/server/content/files/1613838769f3d7---vubipijapopaderigilo.pdfIn PDF document text
    • https://stabiactiv.com/userfiles/file/vatejonifulujitikazukoja.pdfIn PDF document text
    • https://lmetinternationalschool.in/ckeditor/ckfinder/userfiles/files/70828687064.pdfIn PDF document text
    • http://bike-aholic.com/UserFiles/file/butasalipurazizuwarexabi.pdfIn PDF document text
    • http://koslita.eu/ckfinder/userfiles/files/rapefuviwerebomapexido.pdfIn PDF document text
    • https://www.spitalmoldovanoua.ro/ckfinder/userfiles/files/73104851735.pdfIn PDF document text
    • https://pyccenter.com/images/Upload/file/97790826409.pdfIn PDF document text
    • https://clearpatth.com/userfiles/file/26815877854.pdfIn PDF document text
    • http://michelschuurmans.nl/images/uploads/file/potasatanesusi.pdfIn PDF document text
    • http://alrabbancapital.com/file/files/milujuvinixubusa.pdfIn PDF document text
    • https://championsforchildren.org/wp-content/plugins/super-forms/uploads/php/files/68fbbde33e7ef698d657f08a968e516e/wijizoxiwobimavikixudavax.pdfIn PDF document text
    • http://geriatriccarenewjersey.com/userfiles/files/41159184442.pdfIn PDF document text
    • http://erkerlaender.de/wp-content/plugins/formcraft/file-upload/server/content/files/1613c859b56a4b---81484875963.pdfIn PDF document text
    • https://cs-nippon-cp.com/mailmagazine/upload/files/24378239373.pdfIn PDF document text
    • https://billard-hauri.ch/userfiles/file/zodevugogesizodoj.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/FevRqgeaUVY/uplcv?utm_term=uninstall+android+default+appsPDF 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_off0000dac5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDAC5 10600 bytes
SHA-256: 25ef540968aab8005482cbb06e0185bd5297512eae952b00816952d5f3b6bc02
font_01_sfnt_off0000f314.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF314 18072 bytes
SHA-256: 1bb47f7e420df1aa4bb2d63ebca68668831e13fffb775378c1f81a2daedda8a1
font_02_sfnt_off000121b6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x121B6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1