Malicious PDF — malware analysis report

Static analysis result for SHA-256 4d91b599ea4d2cc4…

MALICIOUS

PDF

95.9 KB Created: 2021-09-21 16:49:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 726b3fd9f78f6c6c01c601a7a666bf93 SHA-1: f42a1d324e1d5ab7b04f14a3d712b54a5b9b9bc7 SHA-256: 4d91b599ea4d2cc4f56a0ab3a7c657968ba9d4ac4535f4ac49bc59e5f98039e7
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF document exhibits characteristics of a phishing or redirection attack, evidenced by a link farm pointing to multiple domains, some of which are hosted on compromised CMS uploads and disposable hosting. The embedded JavaScript stream, while not fully analyzed for specific actions, likely contributes to the redirection or obfuscation mechanism. The ClamAV detection as 'Pdf.Phishing.Trojan' further supports a malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://chachachat.info/js/ckfinder/userfiles/files/povopupala.pdf
    • https://www.artikel238.nl/emmwebbit/resources/ckfinder/userfiles/files/25925819199.pdf
    • http://giasuthanhdat.vn/Images_upload/files/82865281724.pdf
    • http://gardens-spa.com/user_pict/file/zutadopitovisawejogituli.pdf
    • http://baominhlabors.com/upload/files/44590048548.pdf
    • https://oknoplus-omsk.ru/wp-content/plugins/super-forms/uploads/php/files/d9251b0b4451d3840f3f5fc34ae18068/26913642520.pdf
    • https://voolabs.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613b3c0d667dd---99971585061.pdf
    • http://perechen-izdaniy.ru/js/ckfinder/userfiles/files/48058744119.pdf
    • https://activepymes.com/pub/file/zifugipomezadixufepija.pdf
    • https://pearproperties.in/userfiles/file/jabadovizini.pdf
    • https://zlatartopalovic.rs/files/ganab.pdf
    • http://le-lemniscus-incandescent.fr/ckeditor/upload/files/vomonewejodep.pdf
    • http://contelex.it/userfiles/files/razufi.pdf
    • https://thietbidiensino.vn/media/ftp/file/78222326800.pdf
    • https://venusnvs.com/userfiles/file/71220131721.pdf
    • https://suavitinhtannha.net/upload/files/79014286624.pdf
    • https://jiu-hang.com/upfiles/editor/files/ruwuxenabirexa.pdf
    • https://briljant-maleri.se/UserFiles/files/26437340042.pdf
    • https://client-sms.com/ckfinder/userfiles/files/44361737537.pdf
    • http://lacasedescaraibes.fr/file/69788047932.pdf
    • https://www.verpoort-bouw.be/wp-content/plugins/formcraft/file-upload/server/content/files/161487578bac41---wepabisixawadalibu.pdf
    • http://caribsplash.org/wp-content/plugins/formcraft/file-upload/server/content/files/161409ff8111c9---34726715527.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BvfzZFkJO3s/uplcv?utm_term=how+to+make+button+more+attractive+in+android
    • 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_off00010e14.bin
ed35f75e2b5d1cc49e6e5747622e2120e80843d5ca6a1bfdf593deeb97869090
pdf-font-stream PDF embedded font (sfnt) at offset 0x10E14 19580 bytes
font_01_sfnt_off000140de.bin
a49f9506e51cc583765a6794a75776c62fbb5cfdff355ab161c35ba81614a266
pdf-font-stream PDF embedded font (sfnt) at offset 0x140DE 10792 bytes
font_02_sfnt_off000159b4.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x159B4 16792 bytes