Malicious PDF — malware analysis report

Static analysis result for SHA-256 c8016d3b7de7e3c0…

MALICIOUS

PDF

94.1 KB Created: 2021-09-04 13:51:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 3714c1253b2e58ef9810c6ac84b7a905 SHA-1: af715104026b010d6ce6247c04ac884488bf1abd SHA-256: c8016d3b7de7e3c02c10d9715f6d94e461c1c558db4f995297a482b947fa6423
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains a link farm pointing to numerous distinct hosts, many of which appear to be compromised WordPress sites or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware distribution. The embedded URLs and the nature of the link farm suggest an attempt to lure users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9968

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 http://quiltingacademy.net/fckeditor/userfiles/file/fokorivafurovupavuzuf.pdf
    • https://twr1115.net/files/fckeditor/file/vipemozeretegejotefu.pdf
    • http://artetendasud.it/userfiles/files/zukigubasusibij.pdf
    • http://budohurtsa.pl/userfiles/file/muzutikotozapemoful.pdf
    • http://mognational.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609a73647ca17---joluxorufofigita.pdf
    • http://ccshecea.org/upload/files/45707934585.pdf
    • http://www.oomewatersport.nl/upload/files/31839774928.pdf
    • https://www.lamuccacompany.com/wp-content/plugins/super-forms/uploads/php/files/8d3d09a137b0ffe7676e2b73a20f88b3/xegirigavamebubipag.pdf
    • http://vasamo.org/pds/userfiles/files/36157442484.pdf
    • http://okmarin.ru/userfiles/file/13383472145.pdf
    • http://exactblue.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b1ade3b337c---toteforegam.pdf
    • http://www.insurancedirectcanada.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16123c436786fb---zezufigusetugajiramaripa.pdf
    • http://superplasticizer.cn/d/files/zadatevonewel.pdf
    • http://rusiuojigalvoji.lt/wp-content/plugins/formcraft/file-upload/server/content/files/1608307f4de986---3075623223.pdf
    • http://creativeindustries.ru/uploads/userfiles/file/18878417070.pdf
    • http://arcadia1973reunion.com/clients/3/33/33cb7023d77084166ed027ca16b579b7/File/birasejaj.pdf
    • https://arrayamed.com/userfiles/file/6035897354.pdf
    • https://burlingame.com/wysiwygfiles/file/22784572264.pdf
    • http://goldmustang.ru/files/files/pisamajatuwelabutevilinaj.pdf
    • http://pc75.net/upfiles/file/1622579915.pdf
    • http://kennyre.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a0fbd6549f3---94131915950.pdf
    • https://shining4u.com/wp-content/plugins/super-forms/uploads/php/files/1ea583769c16de1fe5fbe17e7cda2814/45777199236.pdf
    • http://tfh-filter.hu/_user/file/pefomugeditiwe.pdf
    • http://gibisch.biz/files/files/24785300274.pdf
    • https://www.burit.net/wp-content/plugins/formcraft/file-upload/server/content/files/160c8ea4460442---doxifaboxisatikatugose.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/DOqCt-cVA4I/uplcv?utm_term=isaac+asimov+biografia+pdf
    • 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://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00010509.bin
fc3b6457e8597f5ba6b9db8b73709ed23fc6d1be50db0040387eae98d3bd7048
pdf-font-stream PDF embedded font (sfnt) at offset 0x10509 10740 bytes
font_01_sfnt_off00011d53.bin
86e046f9895cef6022dfe0a2659043ecdce6a13bf852d7f6f287da06823f4058
pdf-font-stream PDF embedded font (sfnt) at offset 0x11D53 19760 bytes
font_02_sfnt_off000150f7.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x150F7 16792 bytes