Malicious PDF — malware analysis report

Static analysis result for SHA-256 b88838d1d45da9ac…

MALICIOUS

PDF

86.2 KB Created: 2021-09-01 20:55:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: ae7dbd5ffc1e273c3e33cc0f1547c5f8 SHA-1: 36b0763a88ef4680cc8d7155bf3b2194a5242939 SHA-256: b88838d1d45da9acad98444ac551e5db637a66828dd18bd9701bc4e49d46677b
156 Risk Score

Malware Insights

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

The PDF contains a link farm pointing to multiple compromised WordPress sites, which in turn host other PDFs. This suggests a phishing or malware distribution campaign where the initial PDF serves as a lure to further malicious content. The ML classifier and ClamAV detection strongly indicate malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://training-solutions.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1609decb89fae7---31815418989.pdf In PDF document text
    • http://www.nanodrywash.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608a62223ebd4---53124469824.pdfIn PDF document text
    • http://ljhalls.com/wp-content/plugins/super-forms/uploads/php/files/66a4427aebc7b3e60b39570cacf4ebf7/1134598777.pdfIn PDF document text
    • https://organicfertilizerproduction.com/d/files/70244084637.pdfIn PDF document text
    • http://serendipityorlando.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607823f454a0a---30750310312.pdfIn PDF document text
    • http://3handseg.com/wp-content/plugins/formcraft/file-upload/server/content/files/16105d4c9ebf67---lenekaguvipovixoxosukoti.pdfIn PDF document text
    • https://heykidsletscook.info/wp-content/plugins/super-forms/uploads/php/files/a8add2d2d04cfb16fe7e601ac2e98985/lumuravirurumul.pdfIn PDF document text
    • https://leo.tw/upload/ckeditor/files/ginuwol.pdfIn PDF document text
    • http://php-lounge.de/userfiles/file/wodawigapudixazijisuzoba.pdfIn PDF document text
    • http://eastindiaspray.com/suvra/eastindia_spray/files/5697312023.pdfIn PDF document text
    • http://www.hgbehringer.de/img/files/files/rapudamafokideseful.pdfIn PDF document text
    • https://www.xtremefitness.com.au/application/third_party/ckfinder/userfiles/files/nokore.pdfIn PDF document text
    • http://cooper1972.com/clients/b/b4/b451ebb09e7e0345645526f893d9a49e/File/93999226210.pdfIn PDF document text
    • https://svetpoznaniyaonline.ru/wp-content/plugins/super-forms/uploads/php/files/99d85a4300738c664422cd1753b63749/80372814215.pdfIn PDF document text
    • https://franchiseharbor.com/files/files/vamimapegezufof.pdfIn PDF document text
    • http://adhdadvisory.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a311fc9011e---63731540179.pdfIn PDF document text
    • https://gamletaarnhuset.no/wp-content/plugins/formcraft/file-upload/server/content/files/160a6d13bdc88e---47664040957.pdfIn PDF document text
    • http://2015.letnifestiwal.pl/ckfinder/userfiles/files/gedanuzodejoxizeripixisev.pdfIn PDF document text
    • http://pokewaveanaheim.com/uploads/files/134574078.pdfIn PDF document text
    • http://bougerpourstarlight.org/clients/c/c6/c668404594a1c08d975ab50c7bec58f6/File/liwutedolutinat.pdfIn PDF document text
    • http://emmanuelmissionarybaptist.com/clients/74938/File/52671546640.pdfIn PDF document text
    • https://miaousland.fr/ckfinder/userfiles/files/93665957673.pdfIn PDF document text
    • https://action-roofing.com/wp-content/plugins/super-forms/uploads/php/files/966e700e585accb2e5a3ec98a35a944c/25903887255.pdfIn PDF document text
    • http://testsitehq.com/ckeditor-ckfinder-integration/uploads/files/61242845045.pdfIn PDF document text
    • https://rajatotogroup1.com/contents/files/2729421265.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3CAf4wW3hvY/uplcv?utm_term=beauty+and+the+beast+pantomimePDF 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_off0000ea46.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEA46 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0001025d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1025D 10916 bytes
SHA-256: 51ad60f666f6c661062924b90859655aacde16942867abd09619bec9595bcc6a
font_02_sfnt_off00011b3c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11B3C 18424 bytes
SHA-256: b01a2a72d3c09c010ada8a9cc97d0d6598e4dd3ae52885dbbafb4db96d1fe71b