Malicious PDF — malware analysis report

Static analysis result for SHA-256 85db9fcdf01ae806…

MALICIOUS

PDF

82.8 KB Created: 2021-07-17 05:35:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-13
MD5: 55b709a43cae3d19f7e0afd48aebf372 SHA-1: 2abdacd3560942ee890e269c08728d8fa72da28e SHA-256: 85db9fcdf01ae806690e4a134346510b794ec98b10368e416201035df4b5ae77
156 Risk Score

Malware Insights

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

This PDF file was flagged by multiple heuristics and a machine learning classifier as malicious, with ClamAV identifying it as a phishing trojan. It functions as a link farm, containing numerous URLs pointing to compromised WordPress upload directories and other potentially untrusted hosting. The primary goal appears to be directing users to external, malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

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
  • 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 https://precisionautoandac.com/wp-content/plugins/super-forms/uploads/php/files/d4aed1b9aea818aec4f5c39e2077201f/35762894955.pdf In PDF document text
    • http://smartcookieacademy.com/wp-content/plugins/formcraft/file-upload/server/content/files/16099ec9b695ac---93182137614.pdfIn PDF document text
    • http://dynamic1984.com/user_file/file/xalegosalabugepunuj.pdfIn PDF document text
    • https://www.helpagesl.org/wp-content/plugins/formcraft/file-upload/server/content/files/160afe28e47e05---bozowezipiminox.pdfIn PDF document text
    • https://gtselect.fr/ckfinder/userfiles/files/26142620263.pdfIn PDF document text
    • https://codecs.ro/images/file/bufexipamerukadiraxa.pdfIn PDF document text
    • https://www.xcelsus.de/wp-content/plugins/formcraft/file-upload/server/content/files/160ac68d3b4f46---16036282128.pdfIn PDF document text
    • https://zlato-eu.sk/upload/files/nexarid.pdfIn PDF document text
    • https://torrentclub.vip/wp-content/plugins/super-forms/uploads/php/files/7eseorlb79lffj4vcpbhqpbu8h/kigezudovimim.pdfIn PDF document text
    • http://crystalnymph.by/wp-content/plugins/super-forms/uploads/php/files/0178efdb43054dd12f35dbf8674874f6/selewa.pdfIn PDF document text
    • https://bonpetsupply.com/wp-content/plugins/formcraft/file-upload/server/content/files/160883fd7bcf24---96145682154.pdfIn PDF document text
    • https://www.pferde-fuer-unsere-kinder.de/wp-content/plugins/formcraft/file-upload/server/content/files/160713cf61a6d6---zegiwub.pdfIn PDF document text
    • https://www.gsccn.it/wp-content/plugins/formcraft/file-upload/server/content/files/1608420d25a270---pifegexinudaw.pdfIn PDF document text
    • https://reniuved.it/file/funona.pdfIn PDF document text
    • http://bertoniamministrazione.it/bertoni/public/file/48526360870.pdfIn PDF document text
    • http://xperion.hu/wp-content/plugins/super-forms/uploads/php/files/c842a6a5fbc76f1566375d29a08a8a35/85601151308.pdfIn PDF document text
    • http://ankaser.com/userfiles/file/fatuvu.pdfIn PDF document text
    • https://www.lumisolar.pe/wp-content/plugins/formcraft/file-upload/server/content/files/160a8c72f4bffe---23903863261.pdfIn PDF document text
    • http://trainternational.in/wp-content/plugins/formcraft/file-upload/server/content/files/160b739d9158ff---dizuloredexotomebodimenob.pdfIn PDF document text
    • http://zoop-tech.com/ckfinder/userfiles/files/77222441378.pdfIn PDF document text
    • http://www.skup.it/wp-content/plugins/formcraft/file-upload/server/content/files/1606d9d930ade3---76828573497.pdfIn PDF document text
    • https://creationstationdance.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ece5506798e---15452557307.pdfIn PDF document text
    • https://franchiseharbor.com/files/files/29073185784.pdfIn PDF document text
    • http://bakoca.hu/files/file/76238979093.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1KS0DP0cxss/uplcv?utm_term=accounting+cost+does+not+include+mcqPDF 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_off0000e32f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE32F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000fb41.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFB41 16368 bytes
SHA-256: 06088af96449abd5a38d644cae03e58a1525ed59a9f54339bc9a93f979656d7d
font_02_sfnt_off000125f1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x125F1 10680 bytes
SHA-256: 067b2ebc2ceb820cfa07f2eb86b002251bb28742663bcf7c9dbcdf1dbf16612d