Malicious PDF — malware analysis report

Static analysis result for SHA-256 d4421a3cecafe894…

MALICIOUS

PDF

71.0 KB Created: 2021-09-30 15:14:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 8956c12f28dfd4a2ac0d2f50b38c5c8e SHA-1: ef78f10e4d95819a419279f917fd6bf6e0cae5ef SHA-256: d4421a3cecafe894a70aa6b0e0fddfac0a46bd41e8267c0c2a54c52c47757ab4
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was detected as malicious by ClamAV and an ML classifier. It contains embedded JavaScript and numerous external URIs, many of which point to compromised WordPress upload directories or disposable hosting, indicating a link farm designed to redirect users. The embedded JavaScript likely facilitates the redirection or further payload delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9965

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://www.urban-quartz.co.uk/wp-content/plugins/super-forms/uploads/php/files/625836cad34bcdff3d637a3bdda63e56/85067620621.pdf In PDF document text
    • https://yuktiedu.com/wp-content/plugins/super-forms/uploads/php/files/2378d027e677e3f08de03342deaafcae/mubiwawididagafefoj.pdfIn PDF document text
    • http://maiodi.com/userfiles/files/83715997973.pdfIn PDF document text
    • http://dancephoto.ru/userfiles/files/wifeno.pdfIn PDF document text
    • http://polins.org/public/userfiles/file/zimir.pdfIn PDF document text
    • https://lotte-ppta.net/beta/assets/file/92593875823.pdfIn PDF document text
    • https://media-get.ru/userfiles/files/215858522.pdfIn PDF document text
    • http://longtra.vn/userfiles/file/45565032024.pdfIn PDF document text
    • https://socardan.com/userfiles/files/nagomedewelu.pdfIn PDF document text
    • http://kystar.net/filespath/files/20210929010050.pdfIn PDF document text
    • http://kfoodntea.com/dataroom/file/sofolanadazunomok.pdfIn PDF document text
    • http://ccswcd.com/userfiles/file/tumisowebuma.pdfIn PDF document text
    • http://accurateverdicts.com/wp-content/plugins/formcraft/file-upload/server/content/files/161495633ec8ef---75487695106.pdfIn PDF document text
    • http://www.qookspot.kitchen/wp-content/plugins/formcraft/file-upload/server/content/files/16131b4bcdcad6---jelosugutu.pdfIn PDF document text
    • http://lehnerkom.de/images/uploaded/file/92062801207.pdfIn PDF document text
    • http://drprdesaihospital.com/uploads/44075547561.pdfIn PDF document text
    • https://doluhosting.com/calisma2/files/uploads/kajekesejasaj.pdfIn PDF document text
    • http://classiccar-jp.com/js/upload/files/nedoxonuxorigim.pdfIn PDF document text
    • https://www.cdsale.org.au/application/third_party/ckfinder/userfiles/files/redizupogogok.pdfIn PDF document text
    • https://cengilli.com/icerik_images/file/66503766281.pdfIn PDF document text
    • http://soluzionebenessere.eu/userfiles/files/96616076078.pdfIn PDF document text
    • http://tourhong.com/FileData/ckfinder/files/20210928_10761C5A17FF02E9.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/S30rS-6n6vg/uplcv?utm_term=robbery+bob+hack+iosPDF link annotation
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000b055.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB055 10472 bytes
SHA-256: f259d5e568a8ebf42804f54193559a6cb0f3a2d337a6d09b080e6d465503b767
font_01_sfnt_off0000c84a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC84A 18224 bytes
SHA-256: 8200fcbee80081eb39f54b1fcce49829330e3e5820a0a8f5e4bd9711b2699a87
font_02_sfnt_off0000f6ff.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF6FF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1