Malicious PDF — malware analysis report

Static analysis result for SHA-256 4aca85bfde65331b…

MALICIOUS

PDF

106.1 KB Created: 2021-07-19 00:18:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: fd3f4a84de39d97ce06baebd7e038dd8 SHA-1: a22c9d2ad192faea179bda8d5db25c10a7acfcca SHA-256: 4aca85bfde65331bb05a8b2208feeb92791f83365e4bfecae85ccb25747abcf2
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a large number of external links, many pointing to compromised WordPress sites and disposable hosting, indicative of a link farm. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware delivery. Although no scripts were explicitly extracted, the PDF structure and link farm behavior are consistent with techniques used to lure users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9929

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://dubigroup.com/admin/fckeditor/editor/filemanager/connectors/upload/file/xulok.pdf In PDF document text
    • https://www.darrellstuckey.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b52658b6b36---wemozurorunubukakoxof.pdfIn PDF document text
    • https://wkd-uk.com/wp-content/plugins/super-forms/uploads/php/files/4e15ff29bc4be39343e5b9df0cfc6663/jelawiwox.pdfIn PDF document text
    • http://cz-synergy.cz/data/file/11827821769.pdfIn PDF document text
    • https://webmenuplus.com/images/file/83662891216.pdfIn PDF document text
    • http://apvn.info/userfiles/file/fomafutubemetazavig.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bbc8b6ca9fa---nejezejabebukabemodovomu.pdfIn PDF document text
    • http://cargo3030.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16094d4c3359b5---82087394829.pdfIn PDF document text
    • https://iguanapools.com.au/wp-content/plugins/super-forms/uploads/php/files/ua6cobv78rv0mi70ml4sb3bj7m/radevijakininukexev.pdfIn PDF document text
    • http://palakkadtourism.in/ckfinder/userfiles/files/80676836459.pdfIn PDF document text
    • https://webmodeli.com/wp-content/plugins/formcraft/file-upload/server/content/files/160aff22347ffe---notuwurejevopesuso.pdfIn PDF document text
    • https://koratspring.com/upload/file/43554473702.pdfIn PDF document text
    • http://inspirationforexcellence.com/clients/66491/File/91711431786.pdfIn PDF document text
    • https://kudamatsu.org/userfiles/file/9390708847.pdfIn PDF document text
    • http://www.dj-csnl.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160a8aebf69f33---67383424011.pdfIn PDF document text
    • http://studiocalcinoni.com/userfiles/files/rolebapijajed.pdfIn PDF document text
    • https://twr1115.net/files/fckeditor/file/47812810483.pdfIn PDF document text
    • https://calldidocta.com/wp-content/plugins/super-forms/uploads/php/files/3a976e1376fee94db08d1ffde71d511f/63810253635.pdfIn PDF document text
    • http://carsongrad75.com/clients/3/35/35717660c32d3dd9b0ffde8f33a19d23/File/95220546004.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a55d3849eb5---zonopaxozenidis.pdfIn PDF document text
    • http://joshuadacosta.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d609af7f299---fekoziguserewedasu.pdfIn PDF document text
    • http://agataklimowska.pl/userfiles/file/fufigode.pdfIn PDF document text
    • https://sv-fin.ru/wp-content/plugins/super-forms/uploads/php/files/5f15f84590b883176fd5a58ff954cc7b/1483967963.pdfIn PDF document text
    • http://wirheiraten.de/images/file/fidonewakaxufi.pdfIn PDF document text
    • https://action-roofing.com/wp-content/plugins/super-forms/uploads/php/files/8cda38e93756bcd05a0612808d0fe802/72990659289.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/zMnd8XtcwSM/uplcv?utm_term=red+fantail+goldfishPDF 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_off00013bb9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13BB9 17932 bytes
SHA-256: 270dc9b1c50bcc3d096a3113c45dc3154ba16e75dc11e28765bc6b5fc07a3a10
font_01_sfnt_off00016b1c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x16B1C 10576 bytes
SHA-256: a45767f81b9373c82dc7e4887e1216d8f7b9f2d198082f297042a63556c114a2
font_02_sfnt_off000182fc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x182FC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1