Malicious PDF — malware analysis report

Static analysis result for SHA-256 5c21d2eb6c57d6cb…

MALICIOUS

PDF

81.8 KB Created: 2021-09-02 13:13:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: aa09d31ffdab7de0adc0670b0fb9a12e SHA-1: ac606c93d89ba4e4dd72a838c1afd1e9a166b531 SHA-256: 5c21d2eb6c57d6cb2588226a6022f91b95a958e20c9579dbc364da312039ec2d
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains numerous embedded URLs, many of which point to compromised or disposable hosting. Heuristics indicate this is a link farm designed to direct users to external sites. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution via these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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://lalitas-thaimassage-spa.de/wp-content/plugins/formcraft/file-upload/server/content/files/16070273858ce6---kozexire.pdf In PDF document text
    • http://clinicaveterinariabilancino.it/userfiles/files/80780590827.pdfIn PDF document text
    • http://aldercrest.com/files/30058539487.pdfIn PDF document text
    • https://aulacvn.com/upload/fck/file/3872974971.pdfIn PDF document text
    • https://drainscovers.com/wp-content/plugins/super-forms/uploads/php/files/ef358a69af37cc85ef4c68d0c8edb3b9/92378012707.pdfIn PDF document text
    • http://ganan10.co.il/wp-content/plugins/formcraft/file-upload/server/content/files/1609e85f4300b0---tetetipepugisajulepojo.pdfIn PDF document text
    • http://www.siscard.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608223624fdcb---jeganopewekuvure.pdfIn PDF document text
    • http://archinfo.ru/uploads/file/ruleditopi.pdfIn PDF document text
    • http://www.fan-consultants.com.tw/ezadmin/ckfinder/userfiles/files/65866341016.pdfIn PDF document text
    • http://bundoreh.com/fckeditor/files/file/lelutenuna.pdfIn PDF document text
    • http://www.mvdisposal.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607c634c9a2ab---pagezop.pdfIn PDF document text
    • http://195exim.com/datas/files/22015712660.pdfIn PDF document text
    • http://acmemask.com/upfiles/editor/files/dejomaniporexejesaradedof.pdfIn PDF document text
    • http://erfaspot.com/resimler/files/goserenurejokabitipajuwe.pdfIn PDF document text
    • http://maility.pl_adresuserfiles/file/bekarewon.pdfIn PDF document text
    • http://starinviter.com/ckimagefiles/80066140036.pdfIn PDF document text
    • http://diodelumi.com/ckfinder/userfiles/files/95859540646.pdfIn PDF document text
    • https://www.southdownscellars.co.uk/ckfinder/userfiles/files/69080324174.pdfIn PDF document text
    • http://www.jhannahs.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608c3ab42f90b---92589032377.pdfIn PDF document text
    • https://dolcezzecaffe.it/file/tomibapi.pdfIn PDF document text
    • https://gilbertems.com/videos/file/vuranukavowowogumewimume.pdfIn PDF document text
    • https://rmdschoolandcollege.com/wp-content/plugins/super-forms/uploads/php/files/j9csrojtnsd2e88qruj9io9kt2/zemixipurofug.pdfIn PDF document text
    • https://duext.com/wp-content/plugins/super-forms/uploads/php/files/ede006cd0c56bcbb7e24ebaf6393ffaf/popoz.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/LPIa9PGmDLg/uplcv?utm_term=automatic+control+systems+ninth+edition+pdfPDF 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_off0000d0a0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD0A0 21276 bytes
SHA-256: 41f119e6ca83070aae012b6c019a991fdcfcd0cea5a65202f5777e4376ffa77d
font_01_sfnt_off0001078b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1078B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011fa2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11FA2 11080 bytes
SHA-256: f6fe100dc286057fefedced116f058acd5affd0b099435edbd2d28c430d286ae