Malicious PDF — malware analysis report

Static analysis result for SHA-256 a9595cbe9f6c0853…

MALICIOUS

PDF

76.9 KB Created: 2021-09-11 18:44:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: ffaa155432438c9d3eeb5aa15cb6eaa9 SHA-1: 4bcd1e54c0256789d8c5a54a35159626ca75cab9 SHA-256: a9595cbe9f6c085317be49c79ad878a66660a65b86150004298d3ad1d72ca87a
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, indicating a high likelihood of malicious intent. The presence of numerous embedded links to external PDF files, coupled with a heuristic indicating a 'download button' lure, suggests a phishing or scam campaign designed to trick users into downloading further malicious content. While no scripts were explicitly extracted, the PDF structure and embedded links are indicative of a malicious workflow.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9908

Heuristics 6

  • 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.
  • 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 http://architettosbaffo.com/userfiles/files/vixanupukimamag.pdf In PDF document text
    • http://studiosiriosrl.it/userfiles/files/70175267304.pdfIn PDF document text
    • http://4reality.cz/userfiles/files/70252571368.pdfIn PDF document text
    • https://citronixdeflection.com/nbloom/fckuploads/file/67900417371.pdfIn PDF document text
    • https://betentour.com/sites/default/files/file/10346918423.pdfIn PDF document text
    • http://www.mariabeckmann.com/fotos/uploads/files/gogobigutodanibup.pdfIn PDF document text
    • https://wecareu.net/ckfinder/userfiles/files/lebaligogilupulukokaluru.pdfIn PDF document text
    • https://shreenatharcade.com/userfiles/file/towalomanogibiwavesijun.pdfIn PDF document text
    • http://texinpack.com/uploadfile/file///2021090200593588.pdfIn PDF document text
    • http://kerekagy.hu/UserFiles/file/30410910393.pdfIn PDF document text
    • http://amexeuro.com/an3_Uploads/file/zudijokulo.pdfIn PDF document text
    • http://www.cenlafilm.com/siteuploads/editorimg/file/semiwisife.pdfIn PDF document text
    • http://ayurveda-shiatsu-nice.com/upload/files/befaferosomifes.pdfIn PDF document text
    • http://jyjwqj.com/uploadfile/file///2021090416521229.pdfIn PDF document text
    • http://bergepkolcsonzo.hu/userfiles/file/61818477840.pdfIn PDF document text
    • https://85097781.com/upload/files/7432295037.pdfIn PDF document text
    • http://lactopad.com/uploads/files/rurogimake.pdfIn PDF document text
    • http://namthangbasaltstone.com/uploads/image/files/96610796182.pdfIn PDF document text
    • http://blueleaves.ru/userfiles/file/juxojewepekokuginexobar.pdfIn PDF document text
    • https://www.budgetskemaet.dk/wp-content/plugins/formcraft/file-upload/server/content/files/16137e5a9e48f0---dopanalojepuvodena.pdfIn PDF document text
    • http://www.sunarmisir.com.tr/wp-content/plugins/super-forms/uploads/php/files/4iubfub6jr97ucsi2dcdaj16a6/28162951556.pdfIn PDF document text
    • http://energy-labels.nl/userfiles/file/2166482001.pdfIn PDF document text
    • http://giprozdraw.ru/ckfinder/userfiles/files/jojajala.pdfIn PDF document text
    • http://dohertylaw.net/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/14473374085.pdfIn PDF document text
    • https://ytdrive.com/CKEdit/upload/files/zakisasekezituw.pdfIn PDF document text
    • http://bacvietexpress.com/upload/userfiles/files/30462375185.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/ngfLrbzwjls/uplcv?utm_term=boss+2+apk+modPDF 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_off0000c5a3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC5A3 10244 bytes
SHA-256: 5d32772408a80d0c5fa7452697e4836f1e777111fffd2e3957d070ec0c2fe77a
font_01_sfnt_off0000dcc7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDCC7 18628 bytes
SHA-256: 387c6fdbe6d7f33855c86afd36061738865f9567d57c7d18db80702d96de6870
font_02_sfnt_off00010dfc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10DFC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1