Malicious PDF — malware analysis report

Static analysis result for SHA-256 36c84812aacbfd31…

MALICIOUS

PDF

107.3 KB Created: 2021-09-02 11:47:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 908e90176d1f67ec2d898cac25ab0f84 SHA-1: 01412223ae2fc51a3b41422d9e655cee19192c35 SHA-256: 36c84812aacbfd31e2699c2e0569ad392602c3118d15ead291ba78da38889c01
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous URLs pointing to potentially compromised or disposable hosting, suggesting a phishing or malware distribution campaign. The presence of PDF-specific heuristics like 'PDF_SEO_DISPOSABLE_LINK_FARM' and 'PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM' further supports this, indicating the PDF is part of a link farm designed to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9933

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://infrive.ru/uplcv?utm_term=apple+annual+report+2013+pdf PDF link annotation
    • https://sapsda.com/SapmaUserfiles/file/18055499876.pdfIn PDF document text
    • https://isabellepieman.com/userfiles/file/parigotawidozurazuvowapat.pdfIn PDF document text
    • http://driver-jazda.pl/upload/file/dexitusojolufefaxelal.pdfIn PDF document text
    • https://www.cocochan.com.pk/wp-content/plugins/super-forms/uploads/php/files/b223706734bbfeca9ec238e6806fd150/wipuxelewo.pdfIn PDF document text
    • http://xn--80aafmoni2biho.xn--p1ai/admin/ckfinder/userfiles/files/70262824162.pdfIn PDF document text
    • http://hotdeals24x7.com/ci/userfiles/files/4504620.pdfIn PDF document text
    • http://fsanaq.com/upload/file/210815063149531252m90j56avgygc.pdfIn PDF document text
    • http://circolosilverblufitnessclub.eu/userfiles/files/ratisanaxikixaxu.pdfIn PDF document text
    • https://123kozijnofferte.nl/wp-content/plugins/super-forms/uploads/php/files/6n2e28ucjp6pvl0sg7u48qtj20/49819014113.pdfIn PDF document text
    • http://chinalabware.es/d/files/kuxirakove.pdfIn PDF document text
    • http://zdrowejaja.com/Upload/file/59401108804.pdfIn PDF document text
    • http://dainichiji.com/upload_ckr/files/66284361071.pdfIn PDF document text
    • http://biotledlight.com/userfiles/file///solejubolaxilajaxilif.pdfIn PDF document text
    • http://ventima.ru/userfiles/file/30263884536.pdfIn PDF document text
    • http://modero.vn/upload/files/60726792553.pdfIn PDF document text
    • https://sweetestspaparty.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d6bd42096a8---23423168444.pdfIn PDF document text
    • https://webmodels.studio/wp-content/plugins/formcraft/file-upload/server/content/files/1607b85b10bf40---23077186790.pdfIn PDF document text
    • https://mymovingestimate.com/wp-content/plugins/super-forms/uploads/php/files/79824a8759e0f6039687b5096bb55a8b/11218337551.pdfIn PDF document text
    • http://www.rify.us/cms-uploads/files/3050662751.pdfIn PDF document text
    • https://sanruouvang.net/images/uploaded/file/remopez.pdfIn PDF document text
    • https://stayatrosetta.com/wp-content/plugins/super-forms/uploads/php/files/01k3acv1orej86ovcftl623gg9/zipapomajumutop.pdfIn PDF document text
    • http://www.mtpartnersfl.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608b7e5c85af1---vusezefematepewaneb.pdfIn PDF document text
    • http://ledseoul.com/userData/board/file/dutetitutut.pdfIn PDF document text
    • http://bahtiyardishekimi.com/fckfiles/file/66185912174.pdfIn PDF document text
    • http://sarahscupcakery.com/wp-content/plugins/formcraft/file-upload/server/content/files/16092633d04740---70858632405.pdfIn PDF document text
    • https://oceanflowerhotel.com/uploads/image/files/46252552882.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_off00013cf6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13CF6 10780 bytes
SHA-256: 3d18bef6fc0e36b7afaef662c1df6abc2eb5786561a0f09c5e5df6f3436d9122
font_01_sfnt_off0001560e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1560E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00016e20.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x16E20 18708 bytes
SHA-256: b27d153694b137d3e298ebbed084929dd8379849c5aec7a425186affe5c5897e