Malicious PDF — malware analysis report

Static analysis result for SHA-256 4c30bc926027a017…

MALICIOUS

PDF

115.0 KB Created: 2021-09-20 17:28:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: 59d06befe414951cf134aa9eb4f462b7 SHA-1: 20c0b3add32f0100ee8b17f4faa2447d3d4a8957 SHA-256: 4c30bc926027a0177ddb89258ee2d600788a83f940dcabd06e4271a0d667141b
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was flagged by ML and ClamAV as malicious, with critical and high severity heuristics indicating its suspicious nature. The presence of embedded JavaScript and a large number of external URIs, many pointing to potentially disposable domains, strongly suggests a phishing or malware distribution attempt. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic further supports this, indicating a link farm on disposable hosting.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9971

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://repairbase.net/FCKeditor/editor/filemanager/connectors/php/images/file/7880098913.pdf In PDF document text
    • http://mycoapaisyl.com/webimages/files/dipisivuwagod.pdfIn PDF document text
    • https://www.alitec.es/js/ckfinder/userfiles/files/xezisimimur.pdfIn PDF document text
    • http://textingrights.com/userfiles/files/nogasaxamemuditon.pdfIn PDF document text
    • http://ufnk.fr/app/webroot/files/file/85037340053.pdfIn PDF document text
    • http://peoplefineart.com/assets/202109/files/20210905072419745178.pdfIn PDF document text
    • https://itracmediav5.com/ckfinder/userfiles/files/94454761774.pdfIn PDF document text
    • https://ropaalmayoreo.com/images/userfiles/file/lilimanedonajuxezudar.pdfIn PDF document text
    • http://palletgoanloi.com/img-dn/files/92969309165.pdfIn PDF document text
    • https://cliniquemyo.com/userfiles/file/92299604465.pdfIn PDF document text
    • https://mps-india.com/userfiles/files/lawobipifedu.pdfIn PDF document text
    • http://krakow4you.pl/krakow/files/vokafep.pdfIn PDF document text
    • http://jezirka-biobazeny.cz/UserFiles/File/47609310034.pdfIn PDF document text
    • http://cataga.de/beta/files/file/bafizexazelob.pdfIn PDF document text
    • https://mavismanagement.com/wp-content/plugins/formcraft/file-upload/server/content/files/161373901e9fdf---55327137193.pdfIn PDF document text
    • http://ambvetbrashersclavoghisu.eu/userfiles/files/9168287388.pdfIn PDF document text
    • https://777mto.com/contents/files/30812814171.pdfIn PDF document text
    • http://wwpokebar.com/uploads/files/jikusupurawedisimofop.pdfIn PDF document text
    • http://hoanhaochemical.com/uploads/files/96602682433.pdfIn PDF document text
    • http://flairpens.ru/uploads/files/sunojofa.pdfIn PDF document text
    • http://sbstroy53.ru/img/files/52883718577.pdfIn PDF document text
    • https://ikitellirezistans.com/upload/files/sozovenedafib.pdfIn PDF document text
    • http://factory-01.com/js/upload/files/sozosaguvoparixo.pdfIn PDF document text
    • https://dungcuruamui.com/wp-content/plugins/super-forms/uploads/php/files/eh03g6bk497vk87hcuclsrb0ke/kewimaroxavijexinejuw.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3vuEKuznOb8/uplcv?utm_term=verbs+that+start+with+mPDF 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_off00016301.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x16301 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00017b13.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x17B13 16860 bytes
SHA-256: 4c2479f7aa5a936aedf083652dd68b197413fc3e035fb6b45508945bf4672c21
font_02_sfnt_off0001a6d0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1A6D0 10296 bytes
SHA-256: b425e45675e3273e78d1913ec587e88b2b7ef67361b98227aeb0b593df02aaac