Malicious PDF — malware analysis report

Static analysis result for SHA-256 18534b551ca86834…

MALICIOUS

PDF

86.4 KB Created: 2021-09-06 23:01:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 0f8e83d62f5602dc781b455b6357ead6 SHA-1: 7b854d6be0fb4d7348bd3f46e5d366b7e28771cd SHA-256: 18534b551ca86834172c4471885cd8239dfbd72f3bc740079ba95b0b49b5f418
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected by ClamAV as Pdf.Phishing.Trojan and flagged by an ML classifier, indicating malicious intent. It contains numerous links to external websites, many hosted on compromised CMS upload directories, suggesting a link farm or phishing lure. The presence of embedded URLs and the nature of the heuristics point towards an attempt to redirect users to malicious content, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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://www.temsilcisitesi.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d5f9ec5b4df---xamuwejaga.pdf In PDF document text
    • https://www.accidentinjuryalbuquerque.com/wp-content/plugins/super-forms/uploads/php/files/15vch4bp06ui8p25q0hq4fjknc/worizapibipobazetamale.pdfIn PDF document text
    • http://www.fattyweng.com.sg/wp-content/plugins/formcraft/file-upload/server/content/files/1607e88003af43---lapuzabivinebuxogiwisi.pdfIn PDF document text
    • http://bjoybrands.com/wp-content/plugins/formcraft/file-upload/server/content/files/1610e8e5d6f39c---madatukidezojonolopak.pdfIn PDF document text
    • https://cms.blauraum.com/wp-content/plugins/super-forms/uploads/php/files/30681bf11db02aeabea8abb0c9d92d07/wabuxepadumedibiwitejuv.pdfIn PDF document text
    • https://mannoorpally.com/uploads/file/rudanutusod.pdfIn PDF document text
    • http://trumoi-khutrung.com/upload/files/kidax.pdfIn PDF document text
    • http://phillipsbrothersmill.com/clients/6/65/65192871cce8a6e36080a9ebd2808b02/File/talubigevovawekapemub.pdfIn PDF document text
    • http://foto-klub.dk/userfiles/file/21250589093.pdfIn PDF document text
    • http://seosanhrd.com/userfiles/file/lezivupawadezazowamiwap.pdfIn PDF document text
    • https://sthouseluxury.com/upload/files/pedawukabe.pdfIn PDF document text
    • http://www.olympussverige.se/wp-content/plugins/super-forms/uploads/php/files/c7n4mi5m5jkbkug54m6gmqkjb8/vonemasitakenijotekefiwi.pdfIn PDF document text
    • http://kalikraft.com/images/file/11328617253.pdfIn PDF document text
    • https://coebmsf.com/userfiles/file/86506919213.pdfIn PDF document text
    • http://brukikostka.pl/uploads/page/file/28243558413.pdfIn PDF document text
    • http://allegroescrow.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f44df197a2---65008707479.pdfIn PDF document text
    • https://simondaulte.com/ckfinder/userfiles/files/27860533026.pdfIn PDF document text
    • http://monikaknoblochova.com/userfiles/file/jexesedojusaj.pdfIn PDF document text
    • http://wksystems.net/HotelEstimator/userfiles/file/muwilafebu.pdfIn PDF document text
    • http://abacusnancy.com/userfiles/file/zevef.pdfIn PDF document text
    • https://rhagro.com.mx/wp-content/plugins/super-forms/uploads/php/files/97f9faaf1db7df6b1fa0072dc22a627c/depesugexeledifavapazumak.pdfIn PDF document text
    • http://philippinesroadshow.com/wp-content/plugins/super-forms/uploads/php/files/2ea538b77355b05c009a12f79fc4ea44/63180529.pdfIn PDF document text
    • https://iamluno.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606eafffb9f21---wowaxogifobezexekovasizik.pdfIn PDF document text
    • https://www.marthatrotts.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16074c5c32a1db---rololanatubakixupom.pdfIn PDF document text
    • http://utopiasacramento.org/clients/0/07/071cdeedc048305be324eb10ab8031d4/File/85197118811.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BkSY9tpko7c/uplcv?utm_term=pronoun+exercise+with+answer+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_off0000ebb2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEBB2 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off000103c9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x103C9 10960 bytes
SHA-256: 3511a970e362b6039bfbcaf92350343376615d50bb0a13827430a1bfa8179095
font_02_sfnt_off00011d42.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11D42 18080 bytes
SHA-256: 6a442a53c33ce7ac209c98bf779744bf77bea1f4b40bcaad2775b6f7436d7528