Malicious PDF — malware analysis report

Static analysis result for SHA-256 433e09c7110f93a1…

MALICIOUS

PDF

77.7 KB Created: 2021-09-20 00:47:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 6b1d2a43cffa4194261598fe96970d10 SHA-1: b1690e6c3bfcd10cc4eb9a9ed95eb9ac9cbc15fa SHA-256: 433e09c7110f93a1b908b8eeebdbd54da627f5ca667d20e222811f189fa5f8cd
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was identified as malicious by ClamAV and an ML classifier. It contains numerous links to external websites, many of which are hosted on compromised WordPress sites or disposable domains, suggesting a link farm or phishing lure. The presence of PDF_URI and PDF_SEO_DISPOSABLE_LINK_FARM heuristics further supports this. Although no scripts were explicitly extracted, the nature of the URLs and the heuristics indicate an attempt to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

Heuristics 6

  • 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.
  • 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://infrive.ru/uplcv?utm_term=yalla+ludo+mod+apk+latest+version PDF link annotation
    • http://www.peritaonline.es/ckfinder/userfiles/files/pixibodarugupebujafabaxe.pdfIn PDF document text
    • http://a1-automotivegroup.com/upload/files/99571070273.pdfIn PDF document text
    • http://architettotamborra.eu/userfiles/files/nufugolob.pdfIn PDF document text
    • http://iseveranscopy.com/upload/editor/file/3416860409.pdfIn PDF document text
    • http://merlegdoktor.hu/tmp/gujisu.pdfIn PDF document text
    • http://erfanekeshmiri.ir/userfiles/file/11027590472.pdfIn PDF document text
    • https://papiratisk.cz/soubory/12040848392.pdfIn PDF document text
    • http://ressourcengarten.de/azubi/userfiles/files/40804303306.pdfIn PDF document text
    • https://csp-pub.com/stockages/files/tebabunosaf.pdfIn PDF document text
    • http://geobigoni.it/userfiles/files/xomiwiweve.pdfIn PDF document text
    • http://flooroverstock.com/admin/userfiles/file/68662738622.pdfIn PDF document text
    • https://www.geosuiteonline.de/wp-content/plugins/formcraft/file-upload/server/content/files/1613c75c23245d---7519304240.pdfIn PDF document text
    • http://alibabashipping.com/userfiles/file/79383809983.pdfIn PDF document text
    • http://zartmobilia.com/userfiles/file/20210909205033.pdfIn PDF document text
    • http://www.kocay.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/16132ef2571959---kigupudonatazoguputenefu.pdfIn PDF document text
    • http://oecschool.com/userfiles/file/diwumirififaw.pdfIn PDF document text
    • https://alcc.c-zentrix.com/ALCC/mail_attachments/multitenant-ws-01/1/1631289749.pdfIn PDF document text
    • http://malbreil.com/userfiles/file/varikimesosigetilevam.pdfIn PDF document text
    • http://www.chatanakonci.cz/userfiles/file/wizuvusebapuvekopifagina.pdfIn PDF document text
    • http://moskvaznaet.ru/upload/files/40705539379.pdfIn PDF document text
    • http://smenergy.kr/uploaded/file/1605072727613de20b430b1.pdfIn PDF document text
    • http://mfplus.ba/wp-content/plugins/formcraft/file-upload/server/content/files/161386aa882caf---19874944780.pdfIn PDF document text
    • https://netcsemege.hu/ckfinder/userfiles/files/11536917654.pdfIn PDF document text
    • 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_off0000c73d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC73D 10796 bytes
SHA-256: c8b6c6e75cceabd9af299af31e535ed9096ac66e56bba4321273773965abdfa9
font_01_sfnt_off0000e016.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE016 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f828.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF828 18352 bytes
SHA-256: 95b85cdd129a22891b78a8f9de4b21b7558a7caee4f8d194ed633111e29c7d2f