Malicious PDF — malware analysis report

Static analysis result for SHA-256 3f9eb73d3b237dd4…

MALICIOUS

PDF

76.6 KB Created: 2021-06-14 08:37:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-27
MD5: f3c047f2182e9f37507f4016c5744f27 SHA-1: 8f4c43c648a00a3b6c3ff52fa18dea7ef2d69d68 SHA-256: 3f9eb73d3b237dd4a6a0c444726a580c027f225baabe38ee4275c6f294e8eed4
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

This PDF document is identified as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains numerous links to external sites, many hosted on compromised WordPress installations, suggesting it functions as a lure to download further malicious content. The document body, though heavily obfuscated, appears to be a fabricated application letter, a common pretext for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 7

  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://coretry.ru/uplcv?utm_term=application+letter+for+civil+engineer+fresh+graduate PDF link annotation
    • https://aquaticlandscape.com/wp-content/plugins/formcraft/file-upload/server/content/files/160780a9ae1652---wafuwuzezufunemeguvuk.pdfIn PDF document text
    • https://rmissio.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1607fa370b99e5---xerifulerokamelikur.pdfIn PDF document text
    • https://ludifrance.fr/userfiles/file/disagogepibusadu.pdfIn PDF document text
    • http://bjoybrands.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bc73f1ae894---88716242965.pdfIn PDF document text
    • https://forkidsvietnam.vn/wp-content/plugins/super-forms/uploads/php/files/4vos3uqf93s419rle40i5q19aa/24090931578.pdfIn PDF document text
    • https://ballestermultiservicios.com/wp-content/plugins/formcraft/file-upload/server/content/files/160947f16e9dc0---fadapeti.pdfIn PDF document text
    • http://albino-pitti.com/pub_img/file/luxutuvefazuwotiwew.pdfIn PDF document text
    • http://lohsclassof70.com/clients/3/31/31ca850ff086a58b81c8700e10a01852/File/16326756827.pdfIn PDF document text
    • http://dochoiotovn.com/uploads/userfiles/file/befunobadolamubatilix.pdfIn PDF document text
    • http://southportrubbish.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608035615f67e---32219980291.pdfIn PDF document text
    • https://ambientltg.com/wp-content/plugins/super-forms/uploads/php/files/691df7e74b31da9772ee99d036338457/97613387793.pdfIn PDF document text
    • http://www.kidnuri.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c4d7a6a1e93---pewilefuwu.pdfIn PDF document text
    • https://revapackers.com/wp-content/plugins/super-forms/uploads/php/files/mibo8sfj93e79fg6jj73a4i4vk/76270644312.pdfIn PDF document text
    • https://www.lesson-online.org/wp-content/plugins/super-forms/uploads/php/files/u6c1i2oeiv40hm6sluitkkbm20/rotekevuwetojawibijevi.pdfIn PDF document text
    • http://vytvarnyobchod.cz/UserFiles/File/nivofudatojexef.pdfIn PDF document text
    • http://casier-a-bouteilles.com/file/32387320124.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ec07.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC07 5464 bytes
SHA-256: aefd7bf8727b413df7f9331ecd0e3b41b3dea0f7d8924b18a421549627b40cfb
font_01_sfnt_off0000fe9e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFE9E 11316 bytes
SHA-256: 608419c52176fd04606c25008c62cebb0f9a576dc804578e94766aaf172518f4