Malicious PDF — malware analysis report

Static analysis result for SHA-256 6d7c2115070b68b4…

MALICIOUS

PDF

70.8 KB Created: 2021-05-20 11:06:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 90288b60eabafad3b1b1a20c8904fa9b SHA-1: f8ecb4ec082242c6f0610f46cf903baa7d80f014 SHA-256: 6d7c2115070b68b43096a33bdbdeaabfb170751faaf3a34dc943fdcc843a62a7
164 Risk Score

Malware Insights

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

The PDF contains numerous links to external websites, many of which host other PDF files, suggesting a link farm designed to improve search engine rankings for specific queries. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware distribution. The presence of embedded URLs and the heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicate the document is part of a campaign to lure users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9993

Heuristics 7

  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://ketchas.ru/uplcv?utm_term=how+much+time+is+required+to+prepare+for+istqb+foundation+level+exam
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a4f03def00f---dekalipago.pdf
    • https://swotin.com/wp-content/plugins/formcraft/file-upload/server/content/files/160806f6770027---90689809810.pdf
    • https://master.plus/wp-content/plugins/super-forms/uploads/php/files/88867a910935df8fed537eda5a7659c5/dofarija.pdf
    • https://vernadoc.com/wp-content/plugins/super-forms/uploads/php/files/959446e2dbdd3b4922a821391aab4d37/28859163440.pdf
    • https://www.sahabatkeluargahomecare.com/wp-content/plugins/formcraft/file-upload/server/content/files/160988c28eb559---lawopapejilej.pdf
    • http://www.shipsupply.co.mz/wp-content/plugins/formcraft/file-upload/server/content/files/1608bc05b4b4b5---nuwodaz.pdf
    • https://rlvanstory.com/wp-content/plugins/super-forms/uploads/php/files/5e7b49c444530845a5d5d2b6b1dfb788/sazemopunikivexixorojali.pdf
    • https://a2designbg.com/userfiles/file/lawew.pdf
    • http://smithmurdock.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608506b4c491a---tirir.pdf
    • http://victorylimo1.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609e9de1449b8---vewudivimitiseb.pdf
    • https://leo-translate.com.ua/wp-content/plugins/formcraft/file-upload/server/content/files/16096b58520900---51210693627.pdf
    • http://www.iycadana.org/wp-content/plugins/super-forms/uploads/php/files/ij15eo7hp2hbptqgmulginbu36/29271763109.pdf
    • https://www.rockandroll.blog.br/wp-content/plugins/super-forms/uploads/php/files/c2j2nbiojqmraukvnjerjhei14/gebolujovip.pdf
    • http://wakingbeauty.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608195a101486---6716588729.pdf
    • https://slavica.ru/wp-content/plugins/super-forms/uploads/php/files/42f5c59a826a83a53479d8d93e302c63/fudujivupaviraw.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://scripts.sil.org/OFL

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d3cc.bin
825e89742dbe9f41de6d86d6325944add20014229c3be95551505bb77ad096c5
pdf-font-stream PDF embedded font (sfnt) at offset 0xD3CC 5840 bytes
font_01_sfnt_off0000e79a.bin
c2af134825569a9c8533de228722727a5e2690fac1980d39987c3427d360dde5
pdf-font-stream PDF embedded font (sfnt) at offset 0xE79A 11452 bytes