Malicious PDF — malware analysis report

Static analysis result for SHA-256 c22796315d3e8062…

MALICIOUS

PDF

85.6 KB Created: 2021-09-03 13:46:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: f0fc3a6336e4c1d6045a163d52e2765f SHA-1: 6846196808b129bf01810490c7de90f5640cba67 SHA-256: c22796315d3e80627a5ae0b306b3748a5199245802be21452206b3d2fc51c4d5
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains numerous embedded URLs, many pointing to compromised CMS upload storage, suggesting it functions as a link farm designed to redirect users to malicious sites. The presence of PDF_SEO_DISPOSABLE_LINK_FARM heuristic further supports this, indicating a tactic to obscure the final malicious destination.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9912

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 https://www.mobytec.com.br/mobytec/wp-content/plugins/formcraft/file-upload/server/content/files/1608889e0a199e---bebopolutusavalug.pdf In PDF document text
    • https://aryaayur.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b239bfa5237---82586141011.pdfIn PDF document text
    • http://melissajacksonmd.com/wp-content/plugins/formcraft/file-upload/server/content/files/160cb1aeabdba7---33870897162.pdfIn PDF document text
    • https://lemanssrl.it/file/36780227766.pdfIn PDF document text
    • http://canxetaidientu.com/images/file/20117367768.pdfIn PDF document text
    • http://cpspcb.com/uploads/files/31475426491.pdfIn PDF document text
    • http://www.mvdisposal.com/wp-content/plugins/formcraft/file-upload/server/content/files/16083e386446f9---welajoxisewuzana.pdfIn PDF document text
    • http://greenbiotech.vn/uploads/userfiles/file/56996278961.pdfIn PDF document text
    • https://realwebguys.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607a53553e131---zuseduviw.pdfIn PDF document text
    • http://entone.es/wp-content/plugins/super-forms/uploads/php/files/e4093c3a7713a14ec4ee8705668f3579/4015876695.pdfIn PDF document text
    • http://oasis-inwaste.asia/files/file/tawuvitogegalita.pdfIn PDF document text
    • https://www.physioaktivkramer.de/wp-content/plugins/formcraft/file-upload/server/content/files/160bfc0dbb9bbd---42065728468.pdfIn PDF document text
    • https://www.3dreamchurch.com/wp-content/plugins/super-forms/uploads/php/files/53e7c49a5ecf0fea942f4bf9affb5195/tojeboguvalapibadake.pdfIn PDF document text
    • http://startent.ru/SITE/files/editor/file/jidox.pdfIn PDF document text
    • http://teleserviciomalaga.com/ckfinder/userfiles/files/9393645140.pdfIn PDF document text
    • https://incasur.org/temp//files/tixegifuxidulu.pdfIn PDF document text
    • http://fiumevivo.it/userfiles/files/jidimebewis.pdfIn PDF document text
    • https://endobible.com/userfiles/file/96175245532.pdfIn PDF document text
    • http://somsit.com/ckfinder/userfiles/files/48889082444.pdfIn PDF document text
    • https://stancijanegrin.com/UserFiles/files/figudubixasefidedar.pdfIn PDF document text
    • https://shared401k.com/wp-content/plugins/super-forms/uploads/php/files/625edbe7833ee5defbb81a3f601ff066/95354583324.pdfIn PDF document text
    • http://prefinancovaniehypoteky.sk/res/file/99489036607.pdfIn PDF document text
    • https://grup-insaat.com/userfiles/file/13890976570.pdfIn PDF document text
    • https://www.jahnigterbraak.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160766d28a170e---zajixujafuputixasuj.pdfIn PDF document text
    • http://strategie-online.net/catalogue_dynamique/file/88879243434.pdfIn PDF document text
    • http://cokhihoangvinh.com/uploads/userfiles/file/8024504697.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BkSY9tpko7c/uplcv?utm_term=ibps+po+notification+2019+pdf+addaPDF 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_off0000e8f3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE8F3 10888 bytes
SHA-256: b70a735c18abdeeca2f8b432c585a9b3ebb36873f5a2d1adebf9d3376a9a9fe1
font_01_sfnt_off0001021f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1021F 17736 bytes
SHA-256: fb504cc23cefd114d54c83949ce21c4444d2290e1b008ac2a2edc0f707760933
font_02_sfnt_off00013060.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13060 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1