Malicious PDF — malware analysis report

Static analysis result for SHA-256 939e087e0547fbef…

MALICIOUS

PDF

71.7 KB Created: 2021-09-29 09:05:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 4cb44a45c85fb8b7d0afb382f6cf27d6 SHA-1: 6a95cd77a9dcd2fcc9f909c30a31884c8619db7b SHA-256: 939e087e0547fbef9ae2890fd3aa09e4b9c719dec261d199c62e12f30864b8fa
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF file was flagged by ML classifiers and ClamAV as malicious, indicating a high likelihood of malicious intent. The presence of numerous embedded URLs, many pointing to potentially disposable domains, suggests a link farm or phishing campaign. The heuristic PDF_SEO_DISPOSABLE_LINK_FARM specifically highlights the use of multiple distinct hosts with few links per host, a common tactic for SEO poisoning or distributing malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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 http://another-partner.morefriendship.com/upload/files/jiragesigutamulim.pdf In PDF document text
    • http://nanobubblevietnam.com/uploads/userfiles/file/58730706818.pdfIn PDF document text
    • https://brincandoeaprendendo.com/fotosempresa/files/8472221744.pdfIn PDF document text
    • http://nut-shell.net/upload/files/45422036495.pdfIn PDF document text
    • https://bibonatura.com/ckfinder/userfiles/files/59506929843.pdfIn PDF document text
    • https://suacuasathcm.com/uploads/files/loxuratexogote.pdfIn PDF document text
    • http://fratellilongoni.com/userfiles/files/kivevuraranabokuzotebup.pdfIn PDF document text
    • http://christschoolblr.in/userfiles/file/49665750676.pdfIn PDF document text
    • http://entryexpress.online/chapter_images/files/tafavubiwozoxu.pdfIn PDF document text
    • http://www.sunarmisir.com.tr/wp-content/plugins/super-forms/uploads/php/files/2n474jfj9e55de1g328ej3qj92/dilugatusepij.pdfIn PDF document text
    • http://saigonford3s.com/uploads/2021-09-08/images/files/fovun.pdfIn PDF document text
    • http://rayer.cn/d/files/vuwigovetofinawekukufiso.pdfIn PDF document text
    • http://ventilyatsia-v-sochi.ru/ckfinder/userfiles/files/piwaxitatojidonemegome.pdfIn PDF document text
    • https://alternativecarrepair.com/userfiles/file/98850626945.pdfIn PDF document text
    • http://classicalgardenstatues.com/uplds/file/dopexitok.pdfIn PDF document text
    • http://healhumanity.foundation/userfiles/file/lanelajoxifabodivokobob.pdfIn PDF document text
    • http://csaladiegyteruautok.hu/userfiles/files/betipivuzavubojewazo.pdfIn PDF document text
    • http://salamino.pl/userfiles/file/5965400937.pdfIn PDF document text
    • http://kommunikator.nu/demo/userfiles/file///tibilawim.pdfIn PDF document text
    • http://purplebyanki-com.bvirani.com/ckfinder/userfiles/files/68343853773.pdfIn PDF document text
    • http://densayhongngoai.com/uploads/userfiles/file/42121930958.pdfIn PDF document text
    • http://portakalweb.net/home/portakal/public_html/ckfinder/userfiles/files/80162492592.pdfIn PDF document text
    • http://zit-tech.com/userfiles/files/62806762210.pdfIn PDF document text
    • http://nationshield.ae/userfiles/files/4434812579.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3CAf4wW3hvY/uplcv?utm_term=indian+postal+trackingPDF 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_off0000b3f6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB3F6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000cc08.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCC08 17624 bytes
SHA-256: fa3c864dc645c219c406486a565049d689f862c70477924a397f3f098f713575
font_02_sfnt_off0000f924.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF924 10600 bytes
SHA-256: 7ea55c07eb9a88ce64c5c8f6829e30b22ba2adc3dfc761bebda174239f439b33