Malicious PDF — malware analysis report

Static analysis result for SHA-256 843035dac094adaf…

MALICIOUS

PDF

88.0 KB Created: 2021-07-22 20:23:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: e75e7c111415e3747dd13de709aa06b0 SHA-1: 899d991dfaa6608c466183a524a2c33b9c4bcec0 SHA-256: 843035dac094adaf23ef18427448f209bfdef5d69528458a0da9dc9496c1615d
172 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

This PDF was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. The heuristics indicate it functions as a link farm, directing users to various PDF files hosted on compromised WordPress sites. The presence of multiple PDF_SEO_DISPOSABLE_LINK_FARM and PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM firings suggests a tactic to distribute malicious content through seemingly legitimate but compromised infrastructure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

Heuristics 8

  • 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.
  • Urgency / deadline lure low SE_URGENCY_LURE
    Document contains urgency or deadline language ('account will be terminated', 'action required within 24 hours', etc.) — useful context, but low-signal without other findings
  • Fake invoice / payment lure low SE_INVOICE_LURE
    Document contains invoice or payment language paired with an action verb — useful context when combined with link, macro, or attachment indicators
  • 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.idromeccanicasrl.com/idromeccanicasrl.com/wp-content/plugins/super-forms/uploads/php/files/bab8c874740cf15c678798b592569651/zitaxorirogowetob.pdf In PDF document text
    • http://nuraski.pl/wsg/userfiles/88808382590.pdfIn PDF document text
    • http://knoxvillecentralhs1966.com/clients/8/8c/8c0a3a1fea337096d337135aeb812fb1/File/44098119925.pdfIn PDF document text
    • https://incasur.org/temp//files/fogatakisusudig.pdfIn PDF document text
    • https://nanyangtextile.com/userfiles/file/15449112008.pdfIn PDF document text
    • https://sevsport.info/wp-content/plugins/super-forms/uploads/php/files/eda94093e9f18e2d9ccb9756979ccbfe/84954830315.pdfIn PDF document text
    • https://afriqueitnews.com/wp-content/plugins/super-forms/uploads/php/files/a4e7c3fcf0a65e6c2d0d042c4d7a32ee/6118266563.pdfIn PDF document text
    • http://kamerton.nl/clientfiles/89204827623.pdfIn PDF document text
    • http://edilgroupdigiovanni.it/userfiles/files/40848821488.pdfIn PDF document text
    • https://rjiminfra.com/wp-content/plugins/super-forms/uploads/php/files/32668bf581f6e5020c3f595122bd5bf6/mosisesalufogiva.pdfIn PDF document text
    • https://alakharia.com/public_html/userfiles/file/74523485325.pdfIn PDF document text
    • http://supporttmes.com/clients/2/26/2647aeee05d38019bb2ff7af4ee9f9d5/File/subewibi.pdfIn PDF document text
    • https://malashealthcare.com/userfiles/files/10896400448.pdfIn PDF document text
    • http://bizwd.com/wp-content/plugins/formcraft/file-upload/server/content/files/160de2f15ed7a1---31705488870.pdfIn PDF document text
    • http://anhbanglaw.com/userfiles/file/tuvipip.pdfIn PDF document text
    • https://saraelv.no/wp-content/plugins/formcraft/file-upload/server/content/files/1607037dc64f50---91696486814.pdfIn PDF document text
    • http://ontheedgeofnow.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ac2885846a7---27194247994.pdfIn PDF document text
    • http://www.studiolegalefusimorelli.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a6bc96c4fb9---66682862428.pdfIn PDF document text
    • https://www.isgs.org/wp-content/plugins/super-forms/uploads/php/files/c411958d0184d35859fc2f437eac730c/befaf.pdfIn PDF document text
    • https://agribusiness.pk/wp-content/plugins/formcraft/file-upload/server/content/files/160b89e7ba652b---giligo.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/DOqCt-cVA4I/uplcv?utm_term=low+price+share+list+2020PDF 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_off0000f201.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF201 17860 bytes
SHA-256: 4256a9da6e01fc0e76f7c35871c13c88927e12367ba9a5a35de4f4e04fb2dc8e
font_01_sfnt_off0001210e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1210E 10652 bytes
SHA-256: 7e705f46e5d59cfeea565ba86440806aeaaa13a12104b7272860cf92660e3bde
font_02_sfnt_off000139b7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x139B7 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1