Malicious PDF — malware analysis report

Static analysis result for SHA-256 d3a93829bd73c493…

MALICIOUS

PDF

71.9 KB Created: 2021-09-08 13:24:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 870ca1ee50839e24b1ebd2594b1a62ef SHA-1: a36e87d2e4c80147012c62c93018b31c96e0e1dc SHA-256: d3a93829bd73c4939b17667355e8ba7d04f9be6b38868f82f9609f9dec369298
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous external URIs, many of which point to disposable hosting or compromised CMS upload directories, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution. The embedded JavaScript is likely used to facilitate the redirection or obfuscate the malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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 http://aliguoriarchitetto.eu/userfiles/files/xekedijaposeviw.pdf In PDF document text
    • http://www.korayozelguvenlik.com/wp-content/plugins/formcraft/file-upload/server/content/files/161372e994a649---11806287631.pdfIn PDF document text
    • https://luxesystem.site/js/ckfinder/userfiles/files/68605766114.pdfIn PDF document text
    • http://euroteam.vn/ckfinder/userfiles/files/vunaredomorikimefumo.pdfIn PDF document text
    • https://hankilfood.com/userfiles/file/20210903134448.pdfIn PDF document text
    • http://chataphan.com/file_media/file_image/file/nobolizekiv.pdfIn PDF document text
    • http://abpjse.news-read.com/upload/files/momirozokizonasavo.pdfIn PDF document text
    • http://biirbeh.mn/images/content/file/62724972166.pdfIn PDF document text
    • https://hargagila.com/uploads/image/files/71960917323.pdfIn PDF document text
    • http://buren-kompanie.de/userfiles/files/wumov.pdfIn PDF document text
    • http://www.loockuniformes.com.br/home/wp-content/plugins/formcraft/file-upload/server/content/files/16131143101075---49400072130.pdfIn PDF document text
    • https://dnsbp.com/all4help/fckuserfiles/file/58480644449.pdfIn PDF document text
    • http://www.opencalgary.org/wp-content/plugins/formcraft/file-upload/server/content/files/161319d677add5---badefejujimatukododuter.pdfIn PDF document text
    • http://joelcsimonesq.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/30637325787.pdfIn PDF document text
    • http://galantemontagnana.it/ckfinder/userfiles/files/6188411754.pdfIn PDF document text
    • http://wxhsbl.com/ckfinder/userfiles/files/20210903_045758.pdfIn PDF document text
    • https://alsharqcc.com/userfiles/files/51599825986.pdfIn PDF document text
    • http://bangiyaparishadtoronto.ca/bpt/editor/uploadfiles/63895246127.pdfIn PDF document text
    • http://savvyais.com/userfiles/file/firelerifu.pdfIn PDF document text
    • https://dabanbep.tanglehadong.com/upload/files/28263040844.pdfIn PDF document text
    • https://kcss.hu/korosi/userfiles/file/61651205803.pdfIn PDF document text
    • https://grandhotelbulgaria.com/userfiles/file/gojelitizu.pdfIn PDF document text
    • https://shinyjewellers.com/wp-content/plugins/super-forms/uploads/php/files/0ekaokvgoleohvbc1hejs7oetc/59325622938.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/BkSY9tpko7c/uplcv?utm_term=derivatives+worksheet+docPDF 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_off0000b83b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB83B 16452 bytes
SHA-256: 6b606f210545653ffcb7d20c5141319ac8f54a4459d55bb463c75b365607272b
font_01_sfnt_off0000e233.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE233 10564 bytes
SHA-256: 06709a9d8816de92baa28552a7d0101af17dbd84f9ac941fe2330ddfcf71e87b
font_02_sfnt_off0000fa90.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFA90 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1