Malicious PDF — malware analysis report

Static analysis result for SHA-256 cb911d1fa7c29511…

MALICIOUS

PDF

95.1 KB Created: 2021-07-15 11:30:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 54c9313d8a05318ef8a024097041a366 SHA-1: db7a06d1295035e737e0067f2a5f39b827518486 SHA-256: cb911d1fa7c2951192336d0a8413aa66a080f7a7e8e257cdd99a7cae073bc478
184 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a link farm pointing to multiple compromised WordPress sites and disposable domains, suggesting an attempt to distribute malicious content. The ClamAV detection and ML classifier strongly indicate malicious intent, likely phishing or malware delivery. Although no scripts were explicitly extracted, the PDF structure and numerous external links are indicative of a phishing lure designed to trick users into downloading further malicious payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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
  • Clickable URI points to raw IP address medium PDF_URI_IP_LITERAL
    PDF contains a clickable HTTP(S) action whose host is a literal IPv4 address. Legitimate documents normally link to named domains; raw-IP destinations are common in disposable phishing and malware-delivery infrastructure.
  • 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://dollarplus98.com/images/upload/files/90709147727.pdf
    • http://julieesteban.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607c63b11252f---42111915691.pdf
    • https://cspdental.com/wp-content/plugins/super-forms/uploads/php/files/25fbf111db9db4d4c5948b9c4ab3973d/nunasojogonoj.pdf
    • http://www.training4thefuture.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1607de7a4dd188---bunapabusigaporamep.pdf
    • http://skipjackpoke.com/ckfinder/userfiles/files/1162538248.pdf
    • https://duext.com/wp-content/plugins/super-forms/uploads/php/files/6a9dc08ddacd00448c376c96491be74b/22501731405.pdf
    • http://apsara.ru/userfiles/file/11227873709.pdf
    • https://inchirieriavioane.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160798db0363f4---tuxopusodegot.pdf
    • http://xn--e1aazeoc7d.xn--p1ai/images/shared/file/46827755748.pdf
    • https://fobiy.net/wp-content/plugins/super-forms/uploads/php/files/54897f465aa66213def13241f9f3df0c/labamizipaxamu.pdf
    • http://haozuowenwang.com/imagefiles/file/17190251994.pdf
    • http://telekommarketing.com/firme_data/files/2793604606.pdf
    • http://www.logistiekverbeteren.nl/ckfinder/userfiles/files/39637442815.pdf
    • http://alfavit.tv/userfiles/file/burutegarowulivosokobe.pdf
    • https://bselink.com/userfiles/file/nagovifipaposegokopaluza.pdf
    • https://www.ediliziaindustriale.com/wp-content/plugins/formcraft/file-upload/server/content/files/16082037c9b705---pufuliwamakabonidubefe.pdf
    • http://yuhongzg.com/d/files/53954670998.pdf
    • https://www.qbuildsoftware.com/wp-content/plugins/super-forms/uploads/php/files/da5b7162d457864e58dedcf4ca10d182/24820613614.pdf
    • http://dabien.co.kr/wp-content/plugins/formcraft/file-upload/server/content/files/16094a063c61a0---puwuwalegeb.pdf
    • https://nationalcardsolutions.com/wp-content/plugins/formcraft/file-upload/server/content/files/16077bb7f51336---tawikaviwez.pdf
    • http://refta-bg.com/userfiles/file/58610928287.pdf
    • http://104.156.58.56/~web2inbox/wp-content/plugins/formcraft/file-upload/server/content/files/1609efa5a0b5a4---14263697638.pdf
    • http://tktravel.shop/FileData/ckfinder/files/20210630_0E9DCE5D39E8B4B9.pdf
    • https://www.oneirishrover.com/wp-content/plugins/super-forms/uploads/php/files/f47b550266e440f923a69245aed82a39/bosalipateraxejogevodasa.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/BkSY9tpko7c/uplcv?utm_term=list+of+collective+nouns+for+grade+3
    • 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_off00010d9f.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10D9F 16792 bytes
font_01_sfnt_off000125b1.bin
aff4033cf075c52d67fb1573b6c07b7cdb326b6e9d0ea56613295f24fb532bce
pdf-font-stream PDF embedded font (sfnt) at offset 0x125B1 17592 bytes
font_02_sfnt_off000153db.bin
d30bf49147bb1bf6851a9b1e25a047362447be57793a9f81f33dc7e1e02f6dd8
pdf-font-stream PDF embedded font (sfnt) at offset 0x153DB 10944 bytes