Malicious PDF — malware analysis report

Static analysis result for SHA-256 f525296cde62643e…

MALICIOUS

PDF

81.6 KB Created: 2021-09-16 21:19:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 0cc9addc68e97310fa3257ccc154f31c SHA-1: 0c8c7db0b3c0b0c84d58f27e1aa174f256ec9ed0 SHA-256: f525296cde62643e10dba920038f0ec72142bdc0150cc06b03dae889901e55d0
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by multiple heuristics and a machine learning classifier as malicious, with ClamAV identifying it as a phishing trojan. It contains numerous embedded URLs, many of which are part of a link farm hosted on compromised WordPress sites or disposable domains, suggesting an attempt to redirect users to malicious content. The presence of external URIs and link farm characteristics indicates a phishing or malware distribution vector.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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://crysiq.ru/uplcv?utm_term=best+adblock+for+chrome+free+download PDF link annotation
    • http://www.airportlimofortlauderdale.net/wp-content/plugins/formcraft/file-upload/server/content/files/161355d699c6a9---29288443336.pdfIn PDF document text
    • http://bulmarconsult.com/files/77117015617.pdfIn PDF document text
    • http://kosmonautika.ee/ckfinder/userfiles/files/8217119126.pdfIn PDF document text
    • https://regenerateacademy.com/file/risumoguxedokoda.pdfIn PDF document text
    • http://emeat.ru/var/files/furekiwonovewasa.pdfIn PDF document text
    • http://doggystylzgrooming.com/admin/photos/file/jutamunudewulubirolu.pdfIn PDF document text
    • http://vandervalk.reviews/app/webroot/files/userfiles/files/rugonizogarubodiwudek.pdfIn PDF document text
    • http://www.hkwebdesign.com.hk/wp-content/plugins/formcraft/file-upload/server/content/files/161365dc325268---58334411490.pdfIn PDF document text
    • http://sattosushi.com/uploads/files/suvonekisuka.pdfIn PDF document text
    • https://www.idromeccanicasrl.com/idromeccanicasrl.com/wp-content/plugins/super-forms/uploads/php/files/6a2b37194f63b7ff0176b6eadeb79a80/14423245119.pdfIn PDF document text
    • http://acrclubinversores.com/files/galeria/files/79433425362.pdfIn PDF document text
    • http://suliaox.com/v15/Upload/file/2021911919536726.pdfIn PDF document text
    • https://hmv.ir/wp-content/plugins/formcraft/file-upload/server/content/files/16131a6468899b---28183619866.pdfIn PDF document text
    • http://laarakkers.com/ckfinder/userfiles/files/73513257056.pdfIn PDF document text
    • https://semangkamerah.com/contents/files/62305451550.pdfIn PDF document text
    • http://pilatesmystyle.com/userfiles/files/fazifin.pdfIn PDF document text
    • https://tessuno.com/upload/files/6134d424c1c6d.pdfIn PDF document text
    • http://xn--b1adbbbaeqjtsflbfms0e.xn--p1ai/pict/file/refidewetizujaniwumagukul.pdfIn PDF document text
    • https://mantyobras.com/userfiles/file/lojifamo.pdfIn PDF document text
    • https://cepatdaftargroup2.com/contents/files/56163659944.pdfIn PDF document text
    • https://holcom-solar.com/webroot/img/files/20499740875.pdfIn PDF document text
    • http://handinks.com/ckfinder/images_store/files/jukovoxemifusozuwasuzi.pdfIn PDF document text
    • http://old.bgk-meshkova.com/ckeditor/ckfinder/userfiles/files/69473596255.pdfIn PDF document text
    • 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_off0000dc33.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDC33 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f44a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF44A 11020 bytes
SHA-256: bccaa92533a5bbcd263b5aff98816b8803e7a7b4b51b65ed96088f5a4d0289a8
font_02_sfnt_off00010dd6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10DD6 16484 bytes
SHA-256: d2cdd7d55f2ec39ad12cdf96fabee3eb08d9c0776c06e1aa8e25afbfefb1b4a8