Malicious PDF — malware analysis report

Static analysis result for SHA-256 65f12bdead3ca622…

MALICIOUS

PDF

84.1 KB Created: 2021-09-08 21:53:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: fc489c30663291769a11cb7175e0f4e4 SHA-1: c056b1bb6b4b84824aaa3ab1d4fdfef812542d30 SHA-256: 65f12bdead3ca6224eb37eaf95d8ac3634712faaa733145fefe4ea35725f9881
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains a large number of links pointing to various websites, many of which are hosted on domains flagged as compromised or disposable. The ML classifier strongly indicated maliciousness, and the heuristic firings suggest this is a link farm designed to manipulate search engine results or distribute malicious content. No scripts were extracted, but the primary attack vector appears to be social engineering through deceptive links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

Heuristics 5

  • 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://visaonline-vn.com/wp-content/plugins/super-forms/uploads/php/files/8unp08l66pu8tn2uj8i0mobu53/47128265416.pdf In PDF document text
    • http://rkmaster.ru/uploads/files/83650595785.pdfIn PDF document text
    • http://aspbae.org/userfiles/file/fitikevavojelopuro.pdfIn PDF document text
    • http://studiocalcinoni.com/userfiles/files/81702475402.pdfIn PDF document text
    • http://ediljolli.com/userfiles/files/patijenomuxikexu.pdfIn PDF document text
    • http://zgic.ru/!upload/files/jeniparumajufiz.pdfIn PDF document text
    • http://gr-chem.com/upload/files/45366664404.pdfIn PDF document text
    • http://www.firstpages.eu/app/webroot/files/userfiles/files/18476115583.pdfIn PDF document text
    • http://goldcoil.com/uploadfiles/files/11495612034.pdfIn PDF document text
    • http://technology-mp.it/userfiles/files/29305214387.pdfIn PDF document text
    • http://www.goldenlantern.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/161368fd020121---ruridon.pdfIn PDF document text
    • http://ohmamakitchen.com/uploads/files/papajomilotesozozolopex.pdfIn PDF document text
    • https://quatcongnghieput.com/uploads/files/xadorebijodolumesonopal.pdfIn PDF document text
    • http://yournamebadges.com/withyourdog/cms_uploads/file/sukamisupufepotozejanidog.pdfIn PDF document text
    • https://onecre.com/images/content/files/sebagoz.pdfIn PDF document text
    • http://www.colegiometa.net/home/wp-content/plugins/formcraft/file-upload/server/content/files/161380f4b65fa9---59118710605.pdfIn PDF document text
    • http://irk-yoga.ru/upload/files/mepujames.pdfIn PDF document text
    • http://mazraeir.com/images/upload/files/89968718041.pdfIn PDF document text
    • http://www.maderas-navarro.com/ckfinder/userfiles/files/fekodid.pdfIn PDF document text
    • https://www.reparaciondebomba.com.ar/wp-content/plugins/super-forms/uploads/php/files/uus8b6qota097fu46oc38qgc92/mukazipezenexafejizezusa.pdfIn PDF document text
    • http://around-sicily.net/userfiles/file/nozubeziw.pdfIn PDF document text
    • http://backupcenters.com/userfiles/file/bekatemawilegekokara.pdfIn PDF document text
    • http://safaraval.com/basefile/safaravalcom/files/sujawufefurajufagag.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/ngfLrbzwjls/uplcv?utm_term=best+web+browser+for+android+tv+boxPDF 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_off0000e09b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE09B 19032 bytes
SHA-256: 8b8427c0d594368f389f84014c2112ba1fc743b380f585f1ee3934dfca9283e5
font_01_sfnt_off00011211.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11211 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012a28.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12A28 10748 bytes
SHA-256: 029431ca396eac6298e7b0fd911f4e75537f6eeee23d5a90a9fec83d98b04ddf