Malicious PDF — malware analysis report

Static analysis result for SHA-256 4dcefa124e1064da…

MALICIOUS

PDF

74.9 KB Created: 2021-09-07 07:59:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 91b337d784f236ce27593b77f2cf0069 SHA-1: c480e7bed97b02eecf6afe1e0d6070f5bd8d8aa7 SHA-256: 4dcefa124e1064dacf70dd5e6a70b9627509554b36515a33ed27e06a4dfc46f1
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics indicate the PDF functions as a link farm, directing users to multiple external websites, some hosted on compromised CMS uploads. The presence of numerous unknown URLs suggests a phishing or credential harvesting campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9840

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://augustaelectricalwork.com/editorData/file/bupaxuwa.pdf In PDF document text
    • https://clubsecurite.fr/webroot/upload/files/66531315518.pdfIn PDF document text
    • http://showdoimovel.com/files/files/zekegakonuvibapo.pdfIn PDF document text
    • http://www.dnevi-sekretarjev.eu/wp-content/plugins/formcraft/file-upload/server/content/files/160c40b19eaa38---pukejax.pdfIn PDF document text
    • https://hmv.ir/wp-content/plugins/formcraft/file-upload/server/content/files/16071228a4bb94---namizotenot.pdfIn PDF document text
    • http://cl-metalparts.com/d/files/24409352561.pdfIn PDF document text
    • https://ita.kru.ac.th/ckfinder/userfiles/files/nemuletagikexoziwukuvo.pdfIn PDF document text
    • http://thaimassageboy.com/ckfinder/userfiles/files/dimumunu.pdfIn PDF document text
    • http://kaizenlife.com/ckfinder/userfiles/files/pazepawexowojevesomat.pdfIn PDF document text
    • http://kibbkw.com/uploads/file/6337257338.pdfIn PDF document text
    • http://justsayhi365.com/uploads/file/wobunititekupagevumi.pdfIn PDF document text
    • https://www.chartsunlimited.com.ph/wp-content/plugins/formcraft/file-upload/server/content/files/160b24bc0e689b---vugalexox.pdfIn PDF document text
    • http://villkasz.hu/editor_up/zunixobazipujotifesege.pdfIn PDF document text
    • http://sneedfamilyct.com/clients/44919/File/40642717326.pdfIn PDF document text
    • http://studiosimonepantaleo.it/userfiles/files/59851141487.pdfIn PDF document text
    • https://whitesal.com/data/images/file/3640_20210827042724.pdfIn PDF document text
    • http://stacjaregeneracja.pl/userfiles/file/xipine.pdfIn PDF document text
    • http://secretlove.ch/ckfinder/userfiles/files/sadibafosuka.pdfIn PDF document text
    • https://ladychief.com/wp-content/plugins/super-forms/uploads/php/files/73ea93af2e490eea4982f32a83433272/16759157211.pdfIn PDF document text
    • https://wcdt.co.th/wp-content/plugins/super-forms/uploads/php/files/ajoq05rgptq4ckp58p4o2t2gb5/vasido.pdfIn PDF document text
    • https://ruxthai.com/ckfinder/userfiles/files/33023290944.pdfIn PDF document text
    • http://neoneofytou.com/ckfinder/userfiles/files/nixamemoroxipoleginew.pdfIn PDF document text
    • http://www.auditsi.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609835280c8fa---81250973059.pdfIn PDF document text
    • https://zaragozadenoche.es/upload/files/1677672375.pdfIn PDF document text
    • https://dialogueinpraxis.net/files/docs/82612679560.pdfIn PDF document text
    • http://www.infranetltd.com/wp-content/plugins/formcraft/file-upload/server/content/files/16099a75d8b138---vudidoxogavudo.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/A3Ryygt5BCM/uplcv?utm_term=supreme+court+judgement+on+pf+2019+pdfPDF 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_off0000c146.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC146 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d958.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD958 16476 bytes
SHA-256: 5e091ab95da2d19bcff882c92a7c9fe99686fef43dfbaff7cecbe88192521b7d
font_02_sfnt_off00010354.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10354 11264 bytes
SHA-256: dbf82759c5f71af99fdfacce4d705b71723e87465c9c0e289801e96f1c32d535