Malicious PDF — malware analysis report

Static analysis result for SHA-256 35d14903be31d5f1…

MALICIOUS

PDF

77.5 KB Created: 2021-09-04 04:31:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 7831c14c039efa9ae0ffd182c2ad28e5 SHA-1: cd6320e8bdff3cfdd1fefd4b936a6f32d06c8773 SHA-256: 35d14903be31d5f1d162ab6912df96ab50c95c7096e8faa0ccb3a7b666b52e7d
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links to external websites, many of which are identified as hosting other PDFs, suggesting a link farm designed to distribute malicious content. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware distribution. No scripts were extracted, but the structure points to a malicious document delivery mechanism.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9948

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://bestmiamiturf.com/wp-content/plugins/super-forms/uploads/php/files/3d2dc4c8bbf927d2728036426c74d489/rinunin.pdf In PDF document text
    • http://le-lemniscus-incandescent.fr/ckeditor/upload/files/17842455846.pdfIn PDF document text
    • http://noxsun.com/jingkelun/userfiles/files/20210723115520.pdfIn PDF document text
    • http://stonestudio.pl/files/upload/file/5828837659.pdfIn PDF document text
    • http://polymer-optix.de/userfiles/file/27732255891.pdfIn PDF document text
    • http://davidhammerstein.org/userfiles/file/tajosikatet.pdfIn PDF document text
    • https://newat.ru/wp-content/plugins/super-forms/uploads/php/files/8412f8293dcc8878af607fb73e6a7605/lefifixekowozota.pdfIn PDF document text
    • https://ilc.ua/wp-content/plugins/super-forms/uploads/php/files/u6l18muchvgc6ednurs6793hq4/1593340307.pdfIn PDF document text
    • https://hacunamatata.ru/wp-content/plugins/super-forms/uploads/php/files/7d6e5d85df3ad6ff58b1a277faef1f04/75047065763.pdfIn PDF document text
    • http://bahtiyardishekimi.com/fckfiles/file/37713597676.pdfIn PDF document text
    • https://www.mybizwebsites.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d22f3392057---48876386376.pdfIn PDF document text
    • http://contua.org/userfiles/file/94132374881.pdfIn PDF document text
    • https://dtd.com.pk/ckfinder/userfiles/files/xuzired.pdfIn PDF document text
    • http://au-coeur-du-temps.com/userfiles/file/33248803582.pdfIn PDF document text
    • https://jagamimpi.com/contents/files/40872439471.pdfIn PDF document text
    • http://anhbanglaw.com/userfiles/file/womagejekix.pdfIn PDF document text
    • http://www.rolstoellift.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608ebcde99ba5---suvageserugowokebotavado.pdfIn PDF document text
    • https://www.heainc.com/wp-content/plugins/formcraft/file-upload/server/content/files/16073e578d7d1a---78941919105.pdfIn PDF document text
    • http://atya.eu/files/file/15237989034.pdfIn PDF document text
    • http://www.communityheroesproject.org/wp-content/plugins/formcraft/file-upload/server/content/files/1608b0706bdd2d---nomakomotozaxoxarenavumal.pdfIn PDF document text
    • https://rosemonttherapy.health/wp-content/plugins/super-forms/uploads/php/files/3ntlupacc334vm4f0vn1fcah65/72610509851.pdfIn PDF document text
    • https://citronixdeflection.com/nbloom/fckuploads/file/33678996248.pdfIn PDF document text
    • http://karthikeyanjayaram.com/userfiles/file/95276854386.pdfIn PDF document text
    • http://zeguvietnam.com/uploads/ckfinder/files/vexuvanezefudupodujas.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/LPIa9PGmDLg/uplcv?utm_term=manualidades+con+papel+crepe+para+cumplea%C3%B1os+infantilesPDF 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_off0000c481.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC481 11080 bytes
SHA-256: 23a275c13edaf97b9125765d5f106b9bb774e77e969c6705bc35883dca45bbde
font_01_sfnt_off0000de09.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDE09 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f61b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF61B 18788 bytes
SHA-256: e10c38a774ee8be90527bf353262da4a8615a479b108c37d7bcbd65630ca0daa