Malicious PDF — malware analysis report

Static analysis result for SHA-256 74e6574e656861b7…

MALICIOUS

PDF

75.0 KB Created: 2021-09-08 16:15:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 9f184eb55f624de1bc66491939e5f65b SHA-1: 82acd487fc551cd2eb9bba9454aed767452721a2 SHA-256: 74e6574e656861b7d0979e14faac512aed06b6b397e5444e0408fa4762a8af1a
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

This PDF file was flagged by multiple heuristics as malicious, including a critical ClamAV detection and an ML classifier. It contains numerous embedded URLs, with one heuristic specifically identifying it as a link farm on disposable hosting. The primary purpose appears to be directing users to a collection of external PDF files, potentially for SEO poisoning or to serve as a distribution point for further malware.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9907

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://tjchenxing.com/filespath/files/20210904162026.pdf In PDF document text
    • http://aqua4you.hu/userfiles/file/ronufowerovivex.pdfIn PDF document text
    • http://koppeika.ru/userfiles/file/96870236700.pdfIn PDF document text
    • https://lifetides.ca/cambridge/uploads/files/rugotuzefisoxepe.pdfIn PDF document text
    • https://rireenfrance.com/images/upload/files/xukejesawixo.pdfIn PDF document text
    • http://www.pattyn360.com/upload/forum/files/gexirofijilefirugos.pdfIn PDF document text
    • http://geometrarontani.it/userfiles/files/kewefexozigemezugusobe.pdfIn PDF document text
    • http://agrion.org/upload/fichier/34920003311.pdfIn PDF document text
    • http://www.yeosung21.or.kr/ckfinder/userfiles/files/1630482673.pdfIn PDF document text
    • http://archgeo-leszno.pl/uploads/userfiles/files/67907360147.pdfIn PDF document text
    • https://vjlabor.pitscovn.com/uploads/Upload/files/79322252095.pdfIn PDF document text
    • https://infrastone.com/userfiles/files/loridigesanub.pdfIn PDF document text
    • http://www.thelawchamber.com/wp-content/plugins/formcraft/file-upload/server/content/files/16135b11fc3797---fufixedumekag.pdfIn PDF document text
    • http://marikitaberbagi.com/userfiles/file/83332710876.pdfIn PDF document text
    • http://turskazka.ru/ckfinder/userfiles/files/palubojipakajukasew.pdfIn PDF document text
    • http://superfishinglewood.com/uploads/files/56307033495.pdfIn PDF document text
    • http://bjsddesign.com/filespath/files/20210903161642.pdfIn PDF document text
    • http://sushiloverca.com/uploads/files/vobubokokobugif.pdfIn PDF document text
    • http://otestmanager.com/club/data/userfiles/file/20210904201024.pdfIn PDF document text
    • http://greenhere.cn/upload/ckimg/files/202109080253361457.pdfIn PDF document text
    • http://kahasat.cz/data/file/xerarovolaruk.pdfIn PDF document text
    • http://kebirbeton.com/userfiles/file/zagewowiwuvorum.pdfIn PDF document text
    • https://stl-log.com/htdocs/cljr/data/files/vosegaferakobod.pdfIn PDF document text
    • http://uco-kampen.com/media/files/14656557825.pdfIn PDF document text
    • http://changrung.com/ckfinder/userfiles/files/28078551560.pdfIn PDF document text
    • http://hai-bi.com/uploads/files/202109010714391095.pdfIn PDF document text
    • http://candientushinko.com/images/file/lukofowenumivi.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3CAf4wW3hvY/uplcv?utm_term=tromboembolismo+pulmonar+pdf+colombiaPDF 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_off0000be55.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBE55 10888 bytes
SHA-256: 4e60edc780b9f801bef4a1b55f9147417f512981cc098c5bf23465ceeb2ef515
font_01_sfnt_off0000d73a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD73A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000ef4c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF4C 17840 bytes
SHA-256: d776057ab70088c9efe67fd4fae23be60ad8afd95b72f77a76efa2c95d30ca34