Malicious PDF — malware analysis report

Static analysis result for SHA-256 f5b81a82644a3d43…

MALICIOUS

PDF

64.8 KB Created: 2021-09-24 21:20:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 582c9a6cd76f4e5be7a673c91888313c SHA-1: c5839d88b8ab9ae3ab1bfc34d236473a71668089 SHA-256: f5b81a82644a3d43a8bf9e7e7eecbe88eddb1799739d42845ab8734fd9aff13c
154 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links pointing to potentially compromised websites and disposable hosting, indicating a link farm designed to redirect users. The ClamAV detection and ML classifier strongly suggest malicious intent, likely for phishing or distributing further malware. Although no scripts were explicitly extracted, the PDF structure and embedded URLs are indicative of a malicious document, possibly leveraging embedded JavaScript for redirection or exploitation.

Machine Learning

  • Nyx PDF Classifier malicious score 0.5020

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
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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
  • 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://inwebjor.ru/uplcv?utm_term=app+to+convert+pdf+to+kindle+format PDF link annotation
    • http://borneneskontor-landsforening.dk/userfiles/file/rixaxalese.pdfIn PDF document text
    • https://krantiservice.com/ckfinder/userfiles/files/xakegavujekuxewoso.pdfIn PDF document text
    • https://unique.global/wp-content/plugins/super-forms/uploads/php/files/cbf463fcfa868d07d19778b7316992e4/pafelujejuxusomereposu.pdfIn PDF document text
    • http://gabinetortodontyczny.eu/userfiles/file/42070969186.pdfIn PDF document text
    • http://scamps.biz/userfiles/file/57272270340.pdfIn PDF document text
    • http://euro520.net/userfiles/file/1632349372452737372.pdfIn PDF document text
    • http://glamour-nsk.ru/ckfinder/userfiles/files/5283040474.pdfIn PDF document text
    • http://www.lukoilmarine.com/ckfinder/userfiles/files/bamoger.pdfIn PDF document text
    • http://www.loockuniformes.com.br/home/wp-content/plugins/formcraft/file-upload/server/content/files/1613ffec42a5dd---jonufekiderikeripe.pdfIn PDF document text
    • http://tomaszskiba.com/userfiles/file/poponomofowipifijota.pdfIn PDF document text
    • https://sainaudit.mn/File/kasijuwisenenu.pdfIn PDF document text
    • http://digivideos.net/ckfinder/userfiles/files/26398569856.pdfIn PDF document text
    • https://dottoridegregorio.it/public/file/21425301666.pdfIn PDF document text
    • https://dortmundpools.com/contents/files/25723057671.pdfIn PDF document text
    • https://www.willmarareachamber.com/ckfinder/userfiles/files/beluxepebozolopuxoloderak.pdfIn PDF document text
    • http://czerwoneiczarne.pl/files/file/18179459216.pdfIn PDF document text
    • https://ncvpte.in/userfiles/file/83208966237.pdfIn PDF document text
    • https://www.advids.io/wp-content/plugins/formcraft/file-upload/server/content/files/16142c6ea94e51---82194830596.pdfIn PDF document text
    • http://recruiters-zone.com/wp-content/plugins/formcraft/file-upload/server/content/files/16130008ecac5b---4947229953.pdfIn PDF document text
    • http://security-m.jp/tool/images/file/pexetal.pdfIn PDF document text
    • http://hglobaltour.com/FileData/ckfinder/files/20210910_41FA851928026481.pdfIn PDF document text
    • http://fruhmann-elektrotechnik.at/fomususedamuvarodevikure.pdfIn PDF document text
    • http://papierplus.pl/userfiles/file/nowevazikuzimifevu.pdfIn PDF document text
    • http://akcjonariusz.com/UserFiles/file/libomosolugidoxutazazeni.pdfIn PDF document text
    • https://strefaokazji.pl/uploaded/file/68133466898.pdfIn PDF document text
    • https://hoya.hr/UserFiles/file/ravati.pdfIn PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000b201.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB201 14892 bytes
SHA-256: 4665f04e353f9e213932598120fb6f0e8f5a632fa1e4cceb7f143a17577bdcf5
font_01_sfnt_off0000d7b2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD7B2 10752 bytes
SHA-256: 37db13efbceea2f8522eda0f784ed9e5fce1c3a1334c258a584548ee4998ae56