Malicious PDF — malware analysis report

Static analysis result for SHA-256 447451c8eba1d51b…

MALICIOUS

PDF

75.7 KB Created: 2021-09-09 13:52:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 63a5226bba32db226b3f52a14bc44157 SHA-1: 2948bcba00fcac84ad9204fd78bbd077ad6d82df SHA-256: 447451c8eba1d51b3db5c3bc88056c16660a5275324ff0fff585764d6145e6dd
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous links to compromised websites and disposable hosting, suggesting a phishing or malware distribution scheme. The presence of PDF-specific heuristics like 'PDF_SEO_DISPOSABLE_LINK_FARM' and 'PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM' further supports this, as these are common tactics for distributing malicious content via seemingly legitimate but compromised domains.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9971

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://crysiq.ru/uplcv?utm_term=formula+for+the+sum+of+the+first+n+terms+of+a+geometric+sequence PDF link annotation
    • http://crosswaysrecruitment.com/userfiles/file/vizijerobularulajegajix.pdfIn PDF document text
    • https://robustbrakes.com/administrator/imagetemp/file/39513509087.pdfIn PDF document text
    • http://runhouchem.com/upload/files/99495461615.pdfIn PDF document text
    • https://bdblue.com/ckfinder/userfiles/files/12140225780.pdfIn PDF document text
    • https://www.hdontheroadnapoli.it/wp-content/plugins/formcraft/file-upload/server/content/files/1612f2649d4332---nuvote.pdfIn PDF document text
    • http://bankerz.in/qpic/files/50208280906.pdfIn PDF document text
    • http://www.naraihillgolf.com/admin/userfiles/file/mometakumo.pdfIn PDF document text
    • https://businesslife.com/content/files/9223980879.pdfIn PDF document text
    • http://www.optionassurance.ca/wp-content/plugins/formcraft/file-upload/server/content/files/161363487333c2---26466609166.pdfIn PDF document text
    • https://vsetinrally.cz/userfiles/file/88443011613.pdfIn PDF document text
    • http://scissortailfarms.com/wp-content/plugins/formcraft/file-upload/server/content/files/161332329df8f0---wapiluputazerezijekuzen.pdfIn PDF document text
    • http://tgtech-auto.com/userfiles/file/vibixaletoro.pdfIn PDF document text
    • https://nepalihemp.com/ckfinder/userfiles/files/baluroserapevi.pdfIn PDF document text
    • https://alaqart.atelierleuthold.ch/userfiles/files/vukulos.pdfIn PDF document text
    • http://clubselectionvoyages.net/images/file/43259794718.pdfIn PDF document text
    • https://angel-juicer.com/FileData/ckfinder/files/20210905_257FF424CC21AAC2.pdfIn PDF document text
    • http://www.gametimecatering.com/wp-content/plugins/formcraft/file-upload/server/content/files/161389f9a7a7cc---vorinumoxajaba.pdfIn PDF document text
    • http://vigen12.com/userfiles/file/ritodaked.pdfIn PDF document text
    • https://fishuntpesca.it/file/48011768462.pdfIn PDF document text
    • https://cissud.eu/uploads/ck_editor/files/kubodasase.pdfIn PDF document text
    • http://de.ruben.pl/ckfinder/userfiles/files/xilusozojoti.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_off0000c195.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC195 11004 bytes
SHA-256: 3af7e8d7f7bdd5ec05ec1555a63e006ad411907df7501eb26ab2d8c579c7a32d
font_01_sfnt_off0000daa5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDAA5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f2b7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF2B7 17812 bytes
SHA-256: 1de55b8e93ed8fb0e52787479e550d0810394226cda7044f623dc65491b21223