Malicious PDF — malware analysis report

Static analysis result for SHA-256 db229b05f5f2a67d…

MALICIOUS

PDF

73.6 KB Created: 2021-09-01 22:17:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: d622660f2ba76519d4d838c682708931 SHA-1: b3ce9e579a6e2d8178ccdb3f2e66a64529980af3 SHA-256: db229b05f5f2a67d23db32cffbfbbf7208fd8535b72417554248e230396bd79d
156 Risk Score

Malware Insights

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

The PDF contains a large number of links, many pointing to compromised WordPress sites and disposable hosting, indicating a link farm designed to distribute malicious content or phish users. The ML classifier and ClamAV detection strongly support its malicious nature. No scripts were extracted, but the structure and URL analysis are sufficient to determine the attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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://nanyangtextile.com/userfiles/file/kufuvaganalufarizopik.pdf In PDF document text
    • http://kistours.hu/userfiles/file/xetetexegeloxajuvuj.pdfIn PDF document text
    • https://floorco.allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/3f70ca4b0a0139223e9c891ae0165293/51682882323.pdfIn PDF document text
    • http://nutranghongngoc.com/media/ftp/file/kijaninapemujubiwu.pdfIn PDF document text
    • http://kino-profi.com/wp-content/plugins/super-forms/uploads/php/files/1620f40a4adae5dfd463a33b30136c2d/vinalopoziketobagaseref.pdfIn PDF document text
    • http://agavietnam.com/img/files/duzuxikitupefeziduralef.pdfIn PDF document text
    • https://revapackers.com/wp-content/plugins/super-forms/uploads/php/files/28evgv3sfs899p3omthav6h4un/negitifomodemom.pdfIn PDF document text
    • http://vssteel1999.com/ckeditor/userfiles/files/79869454461.pdfIn PDF document text
    • https://marlin-aquarium.ru/ckfinder/userfiles/files/wotuno.pdfIn PDF document text
    • https://wcdt.co.th/wp-content/plugins/super-forms/uploads/php/files/krlqftstp2cbh7o2o4kg1fsdf0/47141652937.pdfIn PDF document text
    • https://reifenscho.de/wp-content/plugins/formcraft/file-upload/server/content/files/1606e3b048f1b2---pamapuk.pdfIn PDF document text
    • https://obermeyer-modemarkt.de/upload/file/80142270922.pdfIn PDF document text
    • http://broadgatecapital.com/userfiles/file/72608832401.pdfIn PDF document text
    • http://oneself.pro/wp-content/plugins/formcraft/file-upload/server/content/files/160ab13412ac45---nimibegatiro.pdfIn PDF document text
    • http://brenna-ski.pl/userfiles/file/sikikowetapi.pdfIn PDF document text
    • http://for-rent-leuven.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b7cde0bcf01---tuzexelupub.pdfIn PDF document text
    • http://jongauger.com/ckfinder/userfiles/files/liwotadimobe.pdfIn PDF document text
    • http://lt101shop.com/userfiles/files/xomamemexuk.pdfIn PDF document text
    • http://alibabashipping.com/userfiles/file/famoremipafew.pdfIn PDF document text
    • http://skuplaptop.pl/wp-content/plugins/formcraft/file-upload/server/content/files/160e0fd4780b1f---varupomuketonafuxodelurol.pdfIn PDF document text
    • https://postelezmasivu-zlin.cz/ckfinder/userfiles/files/gegepa.pdfIn PDF document text
    • http://fratellibeninca.com/images/file/lepebigutezepije.pdfIn PDF document text
    • https://svetpoznaniyaonline.ru/wp-content/plugins/super-forms/uploads/php/files/3752a775004935f932704dd8b6fda0b9/bizemasigaverapigivulime.pdfIn PDF document text
    • http://aucoindeshalles.fr/menu/file/51024236733.pdfIn PDF document text
    • https://advancedbusiness.co/wp-content/plugins/super-forms/uploads/php/files/953cedd8ea5b99323fa31acfbcc44bd1/53812501077.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/PmAiG5ZyT-k/uplcv?utm_term=proverbs+with+explanationPDF 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_off0000bfc2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBFC2 16156 bytes
SHA-256: 811d31e782b8e2e10448b99e764ad642e32aa0182e0752d2dd23fb1de61f53f4
font_01_sfnt_off0000e915.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE915 10744 bytes
SHA-256: d9d7aa8c8832f1f986fb0ed6efcab927928ad017fdab283ca170637b427b7a47
font_02_sfnt_off0001019d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1019D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1