Malicious PDF — malware analysis report

Static analysis result for SHA-256 f139d261695ea212…

MALICIOUS

PDF

82.7 KB Created: 2021-09-16 15:13:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: 9871a5c1e86eccaf692ddf46b1e228d8 SHA-1: f1efc2262dbf381f3e42b431872f3d46ebe991c4 SHA-256: f139d261695ea2120d04dbc85bc8f1c589ea63fdcd4fce9b442a71105b9c7c03
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF file flagged by ClamAV as a phishing trojan. It contains numerous embedded URLs, many of which point to other PDF files hosted on distinct domains, suggesting a link farm or redirection mechanism. The ML classifier also strongly indicated maliciousness. While no scripts were explicitly extracted, the PDF structure and embedded URIs are indicative of a phishing or SEO-based malicious campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9846

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://pelletier-tp.fr/ckfinder/userfiles/files/veredonirakomatituv.pdf In PDF document text
    • http://kwong-cheong.com/userfiles/82069442402.pdfIn PDF document text
    • https://asi-filter.pl/files/file/laxedinuje.pdfIn PDF document text
    • https://houstoncoinclub.org/FCKeditor/file/pofumumuxibo.pdfIn PDF document text
    • https://nakatarikaszel.pl/app/webroot/userfiles/file/tilure.pdfIn PDF document text
    • http://www.tenniscanberra.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16142d5faf0e05---73187117287.pdfIn PDF document text
    • http://micronforgacsolo.hu/UserFiles/file/levowoxeduregebi.pdfIn PDF document text
    • http://vinhosnorte.com/images/files/sajisefeburupuvawimakov.pdfIn PDF document text
    • https://ip-pharma.net/data/files/wesiwasowofuwudij.pdfIn PDF document text
    • http://transporteslaplata.com/imagenes_web/file/vojogafupirakewapuwe.pdfIn PDF document text
    • http://giadinhlaurenso.org/upload/files/13793415378.pdfIn PDF document text
    • http://freeware-software-download.de/uploads/editor/file/javifuvuzinodaviboji.pdfIn PDF document text
    • http://retailpark.bg/uploads/wysiwyg/files/xizizetafobe.pdfIn PDF document text
    • http://www.sunarmisir.com.tr/wp-content/plugins/super-forms/uploads/php/files/g6jvij79s6bdl1s450c4klgmi2/bakulimetu.pdfIn PDF document text
    • http://progettocecinacuore.it/writable/public/userfiles/file/koxitageno.pdfIn PDF document text
    • http://www.culturehousesun.org/photos/file/gowotafadapomevusedotipor.pdfIn PDF document text
    • http://podlahyadvere.sk/editor_uploads/system/files/kimen.pdfIn PDF document text
    • http://retailcop.ca/files/woneginewor.pdfIn PDF document text
    • https://stomatoloska-ordinacija-rijeka.com/files/83729204898.pdfIn PDF document text
    • http://www.hz-kontejnery.cz/ckfinder/userfiles/files/kitevonepoxopuge.pdfIn PDF document text
    • http://yourhealthyanswer.com/ckfinder/userfiles/files/54881240587.pdfIn PDF document text
    • https://twr1115.net/files/fckeditor/file/makarudimewulax.pdfIn PDF document text
    • http://hotelamadeustorino.com/userfiles/files/40508048380.pdfIn PDF document text
    • https://basisangka.com/contents/files/92555581186.pdfIn PDF document text
    • http://myflora888.com/ck_files/files/namitexudase.pdfIn PDF document text
    • https://dalton-english.com/userfiles/file/doxajikevezexojupujagu.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/BvfzZFkJO3s/uplcv?utm_term=paint+3d+android+apkPDF 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_off0000dc2e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDC2E 19036 bytes
SHA-256: 722976e870b6657294fe3b988a3fdd371d69918dc8579599ac61bbe5527c3d01
font_01_sfnt_off00010e03.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10E03 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001261a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1261A 10304 bytes
SHA-256: 808aef63ead5a0aa3f7520ac67aa7dcad3d881795191b5b579f55697fc90463b