Malicious PDF — malware analysis report

Static analysis result for SHA-256 a88728aeda81d2f4…

MALICIOUS

PDF

89.1 KB Created: 2021-06-29 14:12:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-15
MD5: 3914ca49fb3f1fda3f12e0cbf7eaa5bf SHA-1: 68af546ebf494553e3a60cf698d66ae938931226 SHA-256: a88728aeda81d2f441214df1a6c35fbb8d6e8c93033d245c56029f61e13f86ea
156 Risk Score

Malware Insights

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

The PDF file was flagged by multiple heuristics and a machine learning classifier as malicious, with ClamAV identifying it as Pdf.Phishing.Trojan. The file contains a link farm pointing to numerous distinct hosts, many of which are associated with compromised CMS uploads or disposable hosting, suggesting an attempt to obscure the ultimate destination. The primary purpose appears to be directing users to external sites, likely for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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://jandenzobv.com/image_uploads/file/1363659636.pdf In PDF document text
    • http://aucoindeshalles.fr/menu/file/gapafuvenulomukef.pdfIn PDF document text
    • https://betalinktech.com/blmedia/file/73870058754.pdfIn PDF document text
    • http://macphersonproperties.com/clients/876251/File/29880726743.pdfIn PDF document text
    • http://valdhans.cz/userfiles/file/tabonuponanojexepibof.pdfIn PDF document text
    • https://trichynext.com/wp-content/plugins/super-forms/uploads/php/files/9a479630d816f5f2685a9b8d55e8bc51/74524745287.pdfIn PDF document text
    • https://eandjfamilyhealthcenter.com/wp-content/plugins/super-forms/uploads/php/files/2603e8bf15e22f31b7d3a5e950e06818/67029753764.pdfIn PDF document text
    • https://athensviptour.com/wp-content/plugins/super-forms/uploads/php/files/cedfd63f0b702f7f6232ab8ecc1720ad/redutololigigipisular.pdfIn PDF document text
    • https://www.synergyheart2heart.team/wp-content/plugins/super-forms/uploads/php/files/0g8sf4s8p91p1qgg9u977hncna/tafowabarabagigenafedagek.pdfIn PDF document text
    • https://earthideasawnings.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a7e1d9b9a37---salasazive.pdfIn PDF document text
    • https://rrvchefs.com/wp-content/plugins/super-forms/uploads/php/files/e6c0ad57b37bb4acbbcb794fd5bd32d7/4144041078.pdfIn PDF document text
    • http://for-rent-leuven.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607561abc59ae---31072843360.pdfIn PDF document text
    • https://www.expoagrogto.com/wp-content/plugins/super-forms/uploads/php/files/0046rs3kpbru0jgchln1p27dh0/29808600288.pdfIn PDF document text
    • https://www.sharpeningfactory.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a8d77c3b40b---pufafogewevoleziwikakiz.pdfIn PDF document text
    • https://www.reliancecareuk.com/wp-content/plugins/super-forms/uploads/php/files/f0f701adeb05e4c9d7584ab54f6f38d8/87235135972.pdfIn PDF document text
    • http://phillipsbricksalumni.com/clients/56168/File/kuletomaf.pdfIn PDF document text
    • https://artenika.pl/fck/file/31366514374.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/16088b4e3d48bc---likimezogox.pdfIn PDF document text
    • https://sg-design.top/wp-content/plugins/super-forms/uploads/php/files/516e27da5d189bd8d7955bc4104ccd72/lirelukarusuz.pdfIn PDF document text
    • https://amenajarisiconstructii.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1607e8000d1a09---9583075148.pdfIn PDF document text
    • http://www.asejnrtigers.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1608a32a1ab5e4---gibizulajegetuka.pdfIn PDF document text
    • https://www.arphplumbing.co.uk/wp-content/plugins/super-forms/uploads/php/files/9fsmuegqk914pntniaigr82hk2/69829451531.pdfIn PDF document text
    • http://all-pass.com/folder/editor/file/xakewudemosoz.pdfIn PDF document text
    • http://residencecarlofelice.com/userfiles/files/88096436396.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/LPIa9PGmDLg/uplcv?utm_term=point+of+intersection+of+pair+of+linesPDF 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_off0000f501.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF501 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010d18.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10D18 10472 bytes
SHA-256: c6ebd59b028c41e15e899dff0d0adeae848a5d3e66c35654251bddfa7e69dfc2
font_02_sfnt_off00012504.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12504 18512 bytes
SHA-256: f48bf445873ed93a02a316545295824dd77ef4cc765334fc2b4f447d63f4b12d