Malicious PDF — malware analysis report

Static analysis result for SHA-256 5b81e7b702dc2783…

MALICIOUS

PDF

86.0 KB Created: 2021-08-02 01:22:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 57d88b09854240a0b8617711d179ee1a SHA-1: f39758ebcfe775d8d33c7057f4e015877d8d9d0c SHA-256: 5b81e7b702dc27835256a1954ecc4aa0c933db867e448004fd6879ea0b7f945c
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to compromised CMS uploads or are part of a link farm hosted on disposable domains. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or SEO abuse. Although no scripts were explicitly extracted, the PDF structure and embedded links suggest it's designed to redirect users to malicious or deceptive content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

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 https://foundryindia.org/userfiles/file/pazesafixareluvuzugazu.pdf
    • https://www.frontierexim.com/wp-content/plugins/super-forms/uploads/php/files/pb7qkbf3fitdc0q2e3lelrr1mm/71389430515.pdf
    • http://constructionone.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1608f4a5493d91---zoduka.pdf
    • http://www.melodypods.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607468d3c4735---95018299861.pdf
    • https://ailani.org/wp-content/plugins/super-forms/uploads/php/files/93023cbf56f712ddcf530ff6e568e11b/89606420056.pdf
    • http://deauville.ru/files/file/98460049480.pdf
    • http://www.johnknox.ch/wp-content/plugins/formcraft/file-upload/server/content/files/16077fb40773f1---taremexilov.pdf
    • http://gymostrov.org/gymostrov/userfiles/file/39486159266.pdf
    • http://blankheich.de/images/uploads/file/47323003389.pdf
    • http://qianlong99.org/ckfinder/userfiles/files/96850283517.pdf
    • https://pikewallis.no/wp-content/plugins/formcraft/file-upload/server/content/files/160d0511c2eb5d---rekabemonetixuvom.pdf
    • https://glowskincare.net/wp-content/plugins/super-forms/uploads/php/files/00f0ce25741f8bd3c001252cd7683ee3/fanipifasubole.pdf
    • https://haltia.mx/sii/ckfinder/userfiles/files/wuvivugoruv.pdf
    • http://gzmzwl.com/Uploadfiles/files/jipefud.pdf
    • http://toanlinh.vn/upload/files/86901734069.pdf
    • http://praxis-greve-polley.de/web/editor/files/fumukigepajugojoke.pdf
    • https://blv.by/upload/editor/files/kaxur.pdf
    • http://chiangmaicharmingtravel.com/ckfinder/userfiles/files/xinadagujama.pdf
    • https://www.sanier.pl/wp-content/plugins/super-forms/uploads/php/files/5t4kr8t759edt564gng3okhn4q/89649009762.pdf
    • https://eclipsetheaters.com/wp-content/plugins/formcraft/file-upload/server/content/files/16087df1163f1b---rezatax.pdf
    • https://klingende-zeder.de/wp-content/plugins/formcraft/file-upload/server/content/files/1608d574d83f09---pikamezesematirujarokile.pdf
    • http://payassistinc.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608d5d1aef912---23338066925.pdf
    • https://controlcert.se/wp-content/plugins/formcraft/file-upload/server/content/files/16075d58446a82---72998522681.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/S30rS-6n6vg/uplcv?utm_term=ordenar+frases+en+ingl%C3%A9s+desordenadas+pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e9fa.bin
5c992ad62b1dd054e728333e814a3b9b59ba6233ec077567c32c97fa016bdf72
pdf-font-stream PDF embedded font (sfnt) at offset 0xE9FA 10756 bytes
font_01_sfnt_off00010244.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10244 16792 bytes
font_02_sfnt_off00011a56.bin
102e2eeef683b0e9394a23f21bb27b90eb42f3272b1fe3ad405deeef603ff4de
pdf-font-stream PDF embedded font (sfnt) at offset 0x11A56 17984 bytes