Malicious PDF — malware analysis report

Static analysis result for SHA-256 b7342794b4c89ad6…

MALICIOUS

PDF

80.5 KB Created: 2021-09-12 22:45:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 84c73fa5084756b6c76ad1030a7864c0 SHA-1: 3f4f7877e475fd2d5ce2e61c3598414211898e5b SHA-256: b7342794b4c89ad67bea48e4c450504d36556dfee49d32afe6dbf8a0a9d8e253
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous external URLs, many of which are hosted on compromised or disposable domains. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates a tactic to disguise malicious links within seemingly legitimate content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://medvor.ru/uplcv?utm_term=konversi+pdf+ke+excel+online PDF link annotation
    • http://s-pack.kr/userfiles/file/20210902195011.pdfIn PDF document text
    • https://used-machinetools.ro/app/webroot/files/userfiles/files/66557425784.pdfIn PDF document text
    • http://cokhitienvuong.com/uploads/files/3625701121.pdfIn PDF document text
    • http://sirinthepgroup.com/userfiles/file/25910620542.pdfIn PDF document text
    • http://lsbwg.com/ckfinder/userfiles/files/20210912/1249581140.pdfIn PDF document text
    • http://printific.com/images/contentimages/files/94760337157.pdfIn PDF document text
    • http://medizator.ru/ckfinder/userfiles/files/48971937180.pdfIn PDF document text
    • http://familiehollander.nl/images/uploadedimages/file/miwajewawav.pdfIn PDF document text
    • http://efcosmetic.com/uploadfile/files/33939753310.pdfIn PDF document text
    • http://df-2.de/images/daten/file/niwapujeripolisu.pdfIn PDF document text
    • https://monyetjoget.com/contents/files/norifawojaroditorazaxula.pdfIn PDF document text
    • http://totoquynhhuong.com/upload/files/wuroluvavuw.pdfIn PDF document text
    • http://h-st.nl/bestanden/files/zogujubisa.pdfIn PDF document text
    • http://www.blueoak.fr/image/file/44477057888.pdfIn PDF document text
    • http://we2meeting.com/ckfinder/userfiles/publics/files/98211015091.pdfIn PDF document text
    • http://www.icodar.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613428668b158---dupogosefodilumujupe.pdfIn PDF document text
    • http://ttlengenharia.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1613cc0c7e5d93---nexiwibinakujivaz.pdfIn PDF document text
    • http://m-styleauto.com/js/upload/files/sezojivurikinawomifudewam.pdfIn PDF document text
    • http://paradisoseminatrici.it/userfiles/files/57957823206.pdfIn PDF document text
    • http://generaldistco.com/images/file/kunepopubigov.pdfIn PDF document text
    • http://prodesign31.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16137edaa492e9---muzaponibiravexudaligerak.pdfIn PDF document text
    • https://thailonghoang.vn/upload/files/95708725527.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_off0000d4f3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD4F3 18032 bytes
SHA-256: 2669bdee3b57fe56865f8b8e44f906fb235de7a1602d990737c181959311ec20
font_01_sfnt_off0001041f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1041F 10604 bytes
SHA-256: 36facb313c424c3d03400c9ef0b14e08899d33649e6887e136c3c611ba7cd639
font_02_sfnt_off00011c7e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11C7E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1