Malicious PDF — malware analysis report

Static analysis result for SHA-256 5f3b23749e040a6f…

MALICIOUS

PDF

79.5 KB Created: 2021-09-13 20:23:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: bb355fa7c77efb112ab8ec1b9443cf0e SHA-1: 3e0243d43614a706576014a35bdc7f53fb73c342 SHA-256: 5f3b23749e040a6ffc02c91f6bb41ca6e3d8349bfc3a6d0cc795eb3a79bfb3c0
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file contains a large number of embedded URLs, many of which point to disposable hosting or compromised CMS upload storage. The ML classifier and ClamAV detection strongly indicate malicious intent. The primary function appears to be acting as a link farm to distribute traffic to potentially malicious sites, consistent with phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

Heuristics 6

  • 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
  • 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://opusincertum.it/userfiles/files/pelagazerilamoveveza.pdf In PDF document text
    • https://bestcaps99.com/ckfinder/userfiles/files/kujexuligibusorululova.pdfIn PDF document text
    • http://miraesusan.com/ckupload/files/giragasarijep.pdfIn PDF document text
    • https://www.vita-organic.eu/admin/ckfinder/userfiles/files/3656527501.pdfIn PDF document text
    • http://backupcenters.com/userfiles/file/57399009094.pdfIn PDF document text
    • http://v-lukomorie.com/uploader/files/3762255863.pdfIn PDF document text
    • http://actinq.nl/upload/file/risavo.pdfIn PDF document text
    • https://mokshadhamnepal.org/userfiles/files/92883861340.pdfIn PDF document text
    • https://ddmmaze.altruistictech.org/documents/img/upload/files/lomesobubopuworeju.pdfIn PDF document text
    • https://xn-----6kcabagcgfjsxjciriy6alkh6a7aqk.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/131c89944e5154d4d0c31c4b7043d6b6/nugogobi.pdfIn PDF document text
    • http://abwcoliseum.com/uploads/files/lojojod.pdfIn PDF document text
    • http://facyt.com.ar/ckfinder/userfiles/files/83568157453.pdfIn PDF document text
    • https://biblioteka-koneck.pl/ckfinder/userfiles/files/wadasipo.pdfIn PDF document text
    • http://terwaarde.be/ckfinder/userfiles/files/23544426051.pdfIn PDF document text
    • https://binhruamuinanobac.com/wp-content/plugins/super-forms/uploads/php/files/qvu5vhv1ggs4o2agiii6enkkq8/65017642873.pdfIn PDF document text
    • http://hkwwta.org/userfiles/89837966832.pdfIn PDF document text
    • http://apisicul.com/userfiles/files/4445706917.pdfIn PDF document text
    • http://degrossier.nl/uploads/file/65145794186.pdfIn PDF document text
    • https://catequesisnavarra.org/guiarte_userfiles/files/63328085981.pdfIn PDF document text
    • https://seroinstitute.com/wp-content/plugins/super-forms/uploads/php/files/f885b34570fbfa2f548352802d90d0d4/xisesotutakawe.pdfIn PDF document text
    • http://fatamorgana.fr/uploads/assets/file/kalar.pdfIn PDF document text
    • http://www.psstrecno.sk/wp-content/plugins/formcraft/file-upload/server/content/files/1613aed41b280c---baxomexasud.pdfIn PDF document text
    • http://opt-russtd.ru/data_center/upload_pictures/file/kiripowonimovefemudineb.pdfIn PDF document text
    • https://horacebatten.com/ckfinder/userfiles/files/7153092737.pdfIn PDF document text
    • https://gift-edu.ru/wp-content/plugins/super-forms/uploads/php/files/d0bc068194ead4078bd5816f46a83ca1/11690413551.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/fzgW7-mxBc0/uplcv?utm_term=pdf+to+word+on+windowsPDF 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_off0000d59a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD59A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000edac.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEDAC 17436 bytes
SHA-256: f3f8cccb11caed52b4d969f61db516f592bc88e160982422b3bd0171ef56308d
font_02_sfnt_off000119c4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x119C4 10096 bytes
SHA-256: f78b26d8aa37f88c683e57dfe6cf2efa00a576db99bff4e758480f1fc73f8e40