Malicious PDF — malware analysis report

Static analysis result for SHA-256 6d5dea6c35aa4dcc…

MALICIOUS

PDF

84.6 KB Created: 2021-09-14 06:55:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 09ae8a9da6f9ff9a988c17c34f89af1d SHA-1: d6cb19d231e887a62d69121d54be0c7471a0dbe7 SHA-256: 6d5dea6c35aa4dcc1861e997c58a0b42f96be11ea112464b1b4a065d2cdb53e9
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was flagged by a machine learning classifier and ClamAV as malicious, with ClamAV identifying it as a phishing trojan. Heuristics indicate it functions as a link farm, directing users to numerous external URLs, many of which are hosted on disposable domains. The PDF structure and embedded content suggest an attempt to disguise malicious links as legitimate resources, likely to facilitate phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://www.toptalentusa.com/wp-content/plugins/formcraft/file-upload/server/content/files/161348ba41685d---8233181419.pdf In PDF document text
    • http://inteko-tula.ru/f/file/73532540522.pdfIn PDF document text
    • http://vector-food.pl/userfiles/file/dobewadurosepefa.pdfIn PDF document text
    • http://philboyd.com/46111359470.pdfIn PDF document text
    • https://www.burnat-provins.ch/ck/ckfinder/userfiles/files/55646540782.pdfIn PDF document text
    • https://mimpiindah88.com/contents/files/xokapag.pdfIn PDF document text
    • https://kolkataangikar.org/ckfinder/userfiles/files/mamenagurowepenawumobo.pdfIn PDF document text
    • http://murito.fr/ckfinder/userfiles/files/gataxeminegoxegasu.pdfIn PDF document text
    • http://elskup.pl/images/assets/file/tajaxit.pdfIn PDF document text
    • https://conrays.ru/f/data/dejububopekukor.pdfIn PDF document text
    • http://myucmas.com/userfiles/file/suwapelimotapalumizuw.pdfIn PDF document text
    • http://saopauloairporttransfers.com/ckfinder/userfiles/files/jikamuvisibubamovabiruw.pdfIn PDF document text
    • http://netichikawaya.com/userfiles/file/ludifipotubusam.pdfIn PDF document text
    • http://debseven.net/UserFiles/File/tusimibomujizunemutenolo.pdfIn PDF document text
    • https://ottopianos.nl/files/vizaduxagemafonibukulof.pdfIn PDF document text
    • https://vendax.ro/files/file/41000049096.pdfIn PDF document text
    • https://colegiumaniucarei.ro/ckfinder/userfiles/files/zavoxezuvawamajelezeka.pdfIn PDF document text
    • http://bangladeshceramicsociety.com/uploads/editor/files/milekevusopafu.pdfIn PDF document text
    • http://petra-dario.info/upload/datoteke/54067411261.pdfIn PDF document text
    • http://shengnabei.com/uploadfile/file///2021091017142857.pdfIn PDF document text
    • https://ekselantechnology.solutions/ckfinder/userfiles/files/kadowako.pdfIn PDF document text
    • http://ucokampen.com/media/files/44779029654.pdfIn PDF document text
    • http://xn--hy1bt45apoap01a.net/jangheung/userfiles/file/82189485840.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/1KS0DP0cxss/uplcv?utm_term=plus+two+biology+textbook+pdfPDF 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_off0000e56b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE56B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000fd82.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD82 10940 bytes
SHA-256: 4c555b21a33669c7f8389f3455e0a5ca36193a593033419568d2619b054cbd07
font_02_sfnt_off000116bf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x116BF 17888 bytes
SHA-256: cc20bf8434e7df41a30dafe5a0b1afb498c3a2ab0d2c280abc9770676d0524a1