Malicious PDF — malware analysis report

Static analysis result for SHA-256 3e8259ea2d091f56…

MALICIOUS

PDF

82.9 KB Created: 2021-09-07 17:08:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 5951c8ed386df9328859d5912b01ee4f SHA-1: c2a178f9111e7f1b6c182b6c16f699fd733e11f7 SHA-256: 3e8259ea2d091f56fb75798b996c0f3f285d4ed83d43d9e165b86b423a0b3159
156 Risk Score

Malware Insights

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

The sample was detected as malicious by ClamAV and an ML classifier, indicating a high probability of malicious intent. Several heuristics identified the PDF as a link farm pointing to compromised WordPress upload storage and other disposable hosting, suggesting it's designed to redirect users to malicious sites. The embedded URLs, despite some being marked as benign, contribute to the overall pattern of directing users away from the document.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://www.sblending.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160941101ba251---3117163209.pdf In PDF document text
    • http://wbbray.com/wp-content/plugins/formcraft/file-upload/server/content/files/160925439ece98---zedewexanukezenejuve.pdfIn PDF document text
    • https://www.clinicaepilepsia.cl/ckfinder/userfiles/files/35698165811.pdfIn PDF document text
    • http://wcsps.com.tw/ckfinder/userfiles/files/putub.pdfIn PDF document text
    • http://upsshop.ru/ckfinder/userfiles/files/zonutipuvivigomofi.pdfIn PDF document text
    • http://www.vitrierbxl.be/wp-content/plugins/formcraft/file-upload/server/content/files/1609af5efe38c1---gevilefebogon.pdfIn PDF document text
    • http://pnktools-th.org/ckfinder/userfiles/files/4594063856.pdfIn PDF document text
    • http://autoscuolemontagna.it/userfiles/files/zawokedufekinoxelojove.pdfIn PDF document text
    • http://www.onekaddy.com/wp-content/plugins/formcraft/file-upload/server/content/files/160901f62ab26e---69256804667.pdfIn PDF document text
    • https://peiitw.com/Upload/ckeditor/files/44980902755.pdfIn PDF document text
    • https://szalkasszorutacskok.hu/app/webroot/files/content/files/velovadevo.pdfIn PDF document text
    • https://alamansyria.com/userfiles/file/38773152773.pdfIn PDF document text
    • http://www.kickcommerce.com/userfiles/file/29188026922.pdfIn PDF document text
    • http://imailbox.nl/images/uploadedimages/file/marisutenimigeresugele.pdfIn PDF document text
    • http://turksebruiloften.nl/userfiles/file/wilinaz.pdfIn PDF document text
    • http://caryhigh1987.com/clients/41333/File/mezonet.pdfIn PDF document text
    • http://angerdress.store/ckfinder/userfiles/files/12457447637.pdfIn PDF document text
    • https://spaslask.pl/wp-content/plugins/super-forms/uploads/php/files/olshsd49arr4baui8kuhogupsh/48481369447.pdfIn PDF document text
    • http://michianaorchidsociety.org/clients/2/28/2832e32407c795c8d28ffe68102aa18e/File/96199839861.pdfIn PDF document text
    • http://studiopedrazzini.eu/userfiles/files/zaliruwidas.pdfIn PDF document text
    • https://mkting.com.co/wp-content/plugins/super-forms/uploads/php/files/a535ec5f20fc38b534844ab52e8bc376/53110991857.pdfIn PDF document text
    • https://bestofbucerias.com/upload/file/zesozewizopajagi.pdfIn PDF document text
    • http://workprohealth.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608062905cba5---13003618963.pdfIn PDF document text
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a0619455d57---79937028342.pdfIn PDF document text
    • https://pyhm.ca/wp-content/plugins/super-forms/uploads/php/files/h5ejgj35lsqrvn2c197im546ju/45397841117.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/fzgW7-mxBc0/uplcv?utm_term=tejido+epitelial+cubico+simple+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_off0000deed.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDEED 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f6ff.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF6FF 17680 bytes
SHA-256: fec54f5b0c67b98a52f583e1588b25aafbe9efef7940313113927fa3fbcdc4e5
font_02_sfnt_off000124c0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x124C0 10912 bytes
SHA-256: 63a5501fda7dbd0079390ce8e23ec61c9a8603cb74d6bb70a705727986eec4da