Malicious PDF — malware analysis report

Static analysis result for SHA-256 8bcd908461c2b58d…

MALICIOUS

PDF

82.8 KB Created: 2021-09-05 19:29:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: f3fd90dde907e5afb27dcde76ddc4cd4 SHA-1: 75bc0feabb2ed3e9e657d672a8de530a7cc734e8 SHA-256: 8bcd908461c2b58dc0733233d4487a57ce0eef09dd3a641d13086b62bb41def1
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file is identified as malicious by ML classifiers and ClamAV, with multiple heuristics indicating it functions as a link farm pointing to compromised WordPress uploads and disposable hosting. The embedded URLs, such as 'https://crysiq.ru/uplcv?utm_term=the+really+big+book+of+bible+story+coloring+pages+pdf', are likely used to redirect users to phishing or malware-hosting sites. No scripts were extracted, but the PDF structure and URL patterns strongly suggest a phishing or downloader attack.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://crysiq.ru/uplcv?utm_term=the+really+big+book+of+bible+story+coloring+pages+pdf PDF link annotation
    • http://www.cuerpomenteyespiritu.es/wp-content/plugins/formcraft/file-upload/server/content/files/160b4464abf92e---reruvaworakafisijewuxirep.pdfIn PDF document text
    • https://tractorpulling-emmeloord.nl/upload/file/kugumebume.pdfIn PDF document text
    • http://prttour.ca/FileData/ckfinder/files/20210803_0D8725AC034925CD.pdfIn PDF document text
    • http://statsale.com/data/upload/ck/files/puzofisenik.pdfIn PDF document text
    • https://www.tyrtaios.gr/ckfinder/userfiles/files/13395689507.pdfIn PDF document text
    • http://elenasteele.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608146107002d---95486593286.pdfIn PDF document text
    • http://fotosvatba.net/userfiles/file/24019533589.pdfIn PDF document text
    • http://brlairport.com/images/file/65671348631.pdfIn PDF document text
    • https://ceilford.org/wp-content/plugins/super-forms/uploads/php/files/0c1cf94cc8adbd3516a88df8fd7f2a95/bubiguvesivinuluxo.pdfIn PDF document text
    • https://www.mozartcantat.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16124e4c88ae9e---gunerojidimijugejomo.pdfIn PDF document text
    • http://skidubravy.sk/spravca/ckfinder/userfiles/files/4551321431.pdfIn PDF document text
    • https://www.jahnigterbraak.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16075137349423---koruseje.pdfIn PDF document text
    • http://www.eau-msu.ru/ckfinder/userfiles/files/tadomexipibu.pdfIn PDF document text
    • https://realestateconnect.pro/wp-content/plugins/super-forms/uploads/php/files/715338h4ravkh1apph6p3b9mh6/dituremivugukesezepevut.pdfIn PDF document text
    • https://dfa-finanz.de/wp-content/plugins/formcraft/file-upload/server/content/files/1609fa40e78ecb---95645746699.pdfIn PDF document text
    • http://peggylittlelawoffice.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/nowopanof.pdfIn PDF document text
    • http://seoulmenu.com/uploads/files/4433420738.pdfIn PDF document text
    • https://jamiatulbanat.in/wp-content/plugins/formcraft/file-upload/server/content/files/1606cc2f15049e---11111864366.pdfIn PDF document text
    • https://expungemyrecordnj.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609115228d712---3634591843.pdfIn PDF document text
    • http://skncn.com/u/files/luwifik.pdfIn PDF document text
    • http://fabtur.ru/upload/files/45892830492.pdfIn PDF document text
    • https://ddmmaze.altruistictech.org/documents/img/upload/files/vejaluxizobax.pdfIn PDF document text
    • https://vildmarksjagt.dk/userfiles/file/xokefibizaborara.pdfIn PDF document text
    • http://alarcon-v.com/editor_upload_image/file/94981224592.pdfIn PDF document text
    • 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_off0000ddb4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDDB4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f5c6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF5C6 17344 bytes
SHA-256: 623f2cd34493541157c271ecb086b839e75f7a3049e50f82230328c90c46f31e
font_02_sfnt_off000122aa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x122AA 11208 bytes
SHA-256: 30335e78854ea98de3ea8598410ffcc2d5d2e28f4204ed9184c4e3071ce5cc2f