Malicious PDF — malware analysis report

Static analysis result for SHA-256 263fa421bcbba78d…

MALICIOUS

PDF

81.4 KB Created: 2021-09-04 14:06:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 9bd1de98dff3b9efebbec8838b410233 SHA-1: 40cb1309e31b8194a5d8aa5761ca8e1007883c30 SHA-256: 263fa421bcbba78d170b09bdbc8f61fc648d749774e010ccf1400bd900859ea7
156 Risk Score

Malware Insights

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

The PDF file contains a link farm directing users to multiple compromised WordPress sites, which in turn host other PDF files. This behavior is indicative of a phishing or malware distribution campaign, likely initiated via spearphishing. The ClamAV detection and ML classifier strongly support its malicious nature.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://www.asahinafunnels.com/wp-content/plugins/super-forms/uploads/php/files/gopjcfgmdsd6380g36nt1ljlvf/rugutowunepakano.pdf In PDF document text
    • http://cloudinfo01.smartevolve.com/images/ckeditor/files/323626349.pdfIn PDF document text
    • https://mziagroup.com/wp-content/plugins/super-forms/uploads/php/files/fp3iob5m5oodldlutrimihh8nh/69034096331.pdfIn PDF document text
    • http://instalater-macecek.cz/klienti/devel/sneznerolby.cz/ckfinder/userfiles/files/11371183494.pdfIn PDF document text
    • https://forkidsvietnam.vn/wp-content/plugins/super-forms/uploads/php/files/07nkdrhjh9pti4qp4acrkjp70r/zezodisuzuzomuzovo.pdfIn PDF document text
    • http://architettosbaffo.com/userfiles/files/3001243257.pdfIn PDF document text
    • http://teenaramainc.org/clients/875997/File/beluwututovevavoxigigenix.pdfIn PDF document text
    • https://mdteam.se/ckfinder/userfiles/files/76383396248.pdfIn PDF document text
    • http://drinkandshrink.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16093bdf88df66---34729880889.pdfIn PDF document text
    • http://beveragesgs.com/userfiles/file/pewogerilofoxo.pdfIn PDF document text
    • http://animationcoach.com/userfiles/file/tawunajularokezijunanit.pdfIn PDF document text
    • https://lisacutler.com/wp-content/plugins/formcraft/file-upload/server/content/files/16075d5e478c62---77846696383.pdfIn PDF document text
    • http://stavebnevyrobky.sk/www/upload/files/16414689145.pdfIn PDF document text
    • http://mijneigenlift.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1607246ac4af4c---sokut.pdfIn PDF document text
    • http://sun-green.nl/ckfinder/userfiles/files/35252324299.pdfIn PDF document text
    • https://theshairpodcast.com/wp-content/plugins/super-forms/uploads/php/files/350f27b4c6bbad61a6b7284931037a35/mozofegena.pdfIn PDF document text
    • http://www.drop-lok.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609b65983b91d---xifirefevugel.pdfIn PDF document text
    • http://manajrgvaaradhi.com/cms-uploads/files/70592437133.pdfIn PDF document text
    • http://creptiles.dk/userfiles/file/52416450128.pdfIn PDF document text
    • https://www.adcgrain.com/wp-content/plugins/super-forms/uploads/php/files/9507df02b07b4341380156b57ac1fcdd/kizilokijomasoposile.pdfIn PDF document text
    • https://angkagenap.com/contents//files/30428029841.pdfIn PDF document text
    • http://riggi.ru/userfiles/file/10495719216.pdfIn PDF document text
    • http://maxitelt.no/wp-content/plugins/formcraft/file-upload/server/content/files/16082f1c6ae2b3---18673168298.pdfIn PDF document text
    • https://micsys.in/userfiles/file/zuraw.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/fzgW7-mxBc0/uplcv?utm_term=rocket+science+banjo+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_off0000d81a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD81A 10872 bytes
SHA-256: c933f7954faca1ac27121a20d12f4c429eee8edf2f86bb865392146294609c1d
font_01_sfnt_off0000f126.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF126 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010938.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10938 17880 bytes
SHA-256: 9d627dbfd9c7dc7d3f37654dfc417dd6c02e1b2d5178752e57d5049ae5f7366d