Malicious PDF — malware analysis report

Static analysis result for SHA-256 a37611f4431ba491…

MALICIOUS

PDF

85.1 KB Created: 2021-06-25 22:11:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: cf109fcd4c3faf4670be1b137a9a3221 SHA-1: 21f205584c37d9aa21ca8b006476ca7e44f9550b SHA-256: a37611f4431ba49107152c3e3d4dd10bf6f8f9f3daab8fd5ba68f2e3cbcdc1c5
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was flagged by multiple heuristics as malicious, including a ML classifier and ClamAV detection. It contains a link farm pointing to compromised WordPress upload storage and other disposable hosting, suggesting a phishing or malware distribution attempt. The presence of embedded URLs and the 'SE_INVOICE_LURE' heuristic indicate the document's content is designed to trick the user into clicking these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9972

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.
  • 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://signaturetowerpune.com/wp-content/plugins/super-forms/uploads/php/files/a7vjshrlo3bdvihdf9gleqtbk1/gomakexutizuwesinevo.pdf
    • https://dienlanhhonganh.com/images/pic/file/40878298058.pdf
    • https://rjiminfra.com/wp-content/plugins/super-forms/uploads/php/files/22fa7f65e4f4523a14b87017bd4c7466/nupuwisaxi.pdf
    • http://boekenwinkelindex.nl/images/uploads/fuvunuzuj.pdf
    • https://thewentworthco.com/wp-content/plugins/super-forms/uploads/php/files/iclvhbd0shb86a99amkndk22r3/40299528288.pdf
    • http://escolacaritas.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608d17a1c9a5f---taveradowasiwoguwekukuku.pdf
    • http://lamekatus.ee/uploads/ckeditor/files/62133037641.pdf
    • https://blackknowledge.com/wp-content/plugins/super-forms/uploads/php/files/11fa0cc1cebe806a8f3330212efbccfe/bisixadekawavofutil.pdf
    • https://www.formwork.co.uk/wp-content/plugins/super-forms/uploads/php/files/1tumap5idd8l9etp6plgunh8el/63455730663.pdf
    • https://ballestermultiservicios.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606d183176bc0---42564705815.pdf
    • http://kfnmdg.com/upfolder/e/files/20210609044956.pdf
    • https://embassyinvietnam.com/webroot/img/files/vimosexevifoxi.pdf
    • https://fiberglasssupplydepot.com/userfiles/file/bimoxudu.pdf
    • https://wecareu.net/ckfinder/userfiles/files/kepivoro.pdf
    • https://mudateconmigo.cl/wp-content/plugins/super-forms/uploads/php/files/abada52055bb6dfbb8af825921973848/xikiji.pdf
    • https://leicht-spb.ru/wp-content/plugins/super-forms/uploads/php/files/1770d451de2ea9abb32db97fffed2764/tulake.pdf
    • http://www.sunaryem.com.tr/wp-content/plugins/super-forms/uploads/php/files/ta3mf3m9v5mjhu3i6faraagr97/62285167341.pdf
    • https://www.kngroup.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609cf50ac825d---3277474744.pdf
    • http://norilskgu.ru/userfiles/file/911884341.pdf
    • https://finestblogger.de/wp-content/plugins/super-forms/uploads/php/files/liknnspvuipjlave7t38p07ti2/23579276010.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/Om9ozkHLxGw/uplcv?utm_term=monthly+payment+calculator
    • http://lovewhereyoulv.wpengine.com/wp-content/plugins/super-forms/uploads/php/files/b9d6307485782c13cd57b3b6b86bc157/vepufifulini.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_off0000ea0b.bin
75edbfa2e1ab4cea6ebd95424acb12815a53bd7647f53fbcd344dfc0924278f3
pdf-font-stream PDF embedded font (sfnt) at offset 0xEA0B 17392 bytes
font_01_sfnt_off00011755.bin
26046b92a0ac592e9c61eb777bb38a6ff45a89e02c64b4a04aefc4ef0037d7b9
pdf-font-stream PDF embedded font (sfnt) at offset 0x11755 10588 bytes
font_02_sfnt_off00012f5c.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x12F5C 16792 bytes