Malicious PDF — malware analysis report

Static analysis result for SHA-256 91346b42fde6dc63…

MALICIOUS

PDF

95.6 KB Created: 2021-09-13 00:31:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: c07b75ed5641b7c938c5a650bd400288 SHA-1: b0ea73ec7f9910252cbb090ff5982931e4ca931e SHA-256: 91346b42fde6dc630f701dc4277a7b16f15b9d669cd910a223c4e73402466f99
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by ClamAV and an ML classifier as malicious, specifically as a phishing trojan. It contains a large number of embedded URLs, many of which point to disposable domains or link farms, indicating a phishing or malware distribution attempt. The document body is heavily obfuscated and appears to be generated by wkhtmltopdf, suggesting it's not intended for direct user reading but rather as a container for malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9965

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://ketchas.ru/uplcv?utm_term=words+beginning+with+a+that+are+positive PDF link annotation
    • http://xn--j1aii.su/userfiles/file/10457590226.pdfIn PDF document text
    • https://saatyapi.com/upload/ckfinder/files/degomimisapipijon.pdfIn PDF document text
    • http://www.somdattabasu.com/fckimages/file/rodegifejozepokavagivibug.pdfIn PDF document text
    • https://tumujerrusa.com/userfiles/21138278543.pdfIn PDF document text
    • http://www.siscbolivia.com/admin/uploaded/fck/file/58822285279.pdfIn PDF document text
    • https://semsaesp.com/ckfinder/userfiles/files/58458132370.pdfIn PDF document text
    • http://le-lemniscus-incandescent.fr/ckeditor/upload/files/lapotuwufokeloral.pdfIn PDF document text
    • http://vip-cond.ru/userfiles/file/71117896273.pdfIn PDF document text
    • http://alhouti.com/userfiles/file/65669483936.pdfIn PDF document text
    • http://aotwresort.org/ckfinder/userfiles/files/21301717301.pdfIn PDF document text
    • http://ristorantebiscione.com/userfiles/files/futatofofisesodovazarez.pdfIn PDF document text
    • http://alrabbancapital.com/file/files/jumixuguwazexefinurofized.pdfIn PDF document text
    • https://nikunjfoundation.org/ckfinder/userfiles/files/56324238367.pdfIn PDF document text
    • http://highspiritsmusic.com/ckfinder/userfiles/files/nalesubon.pdfIn PDF document text
    • http://compie.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1613284f88a3d5---diwoj.pdfIn PDF document text
    • http://samnakthodrahassob.com/userfiles/file/53699406650.pdfIn PDF document text
    • http://a-range.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16137d3c7cc4c1---bakegepamidotax.pdfIn PDF document text
    • https://ccichn.vn/data/upload/file/bovaru.pdfIn PDF document text
    • https://irrisyst.eu/files/file/53039113496.pdfIn PDF document text
    • http://gonzagafood.com/userfiles/files/gudemof.pdfIn PDF document text
    • http://hijoin.hu/editor_up/nurafuwapuduvo.pdfIn PDF document text
    • http://chiangmai-clean.com/user_img/files/jirixatimitajokiruza.pdfIn PDF document text
    • https://a-metal.e-giant.net/archive/file/files/32300878950.pdfIn PDF document text
    • http://xn----9sbkvfu2aex3d.xn--p1ai/ckfinder/userfiles/files/xutulosozokugudum.pdfIn PDF document text
    • https://agencement-menuiserie-var.fr/stockages/files/71524280429.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_off00010f9b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10F9B 18452 bytes
SHA-256: bee850b218e6e48984aab5eee26d11bb145a5220902fd4d6cba292d0819dd854
font_01_sfnt_off00013eec.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13EEC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00015703.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15703 10912 bytes
SHA-256: 952a6c400f6d6745faf5396f188e515df68e01a1b063e86f87f094bf7b6c2b93