Malicious PDF — malware analysis report

Static analysis result for SHA-256 3640508376d2384b…

MALICIOUS

PDF

76.7 KB Created: 2021-09-29 04:21:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-23
MD5: 9a52868b6d31aa510fed76edbb77499f SHA-1: 98f5af870b63da47badae1a3375ca87f2b449731 SHA-256: 3640508376d2384b2bb80cb17996bad3e522556edd7e6fe0a19a4715d92480ee
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF containing embedded JavaScript, which is a common technique for executing malicious code. The PDF also features a link farm with numerous URLs, many hosted on compromised or disposable domains, indicating a likely phishing or redirection scheme. The ML classifier and ClamAV detection strongly support the malicious verdict.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

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 http://diamantina-joaillerie.com/ckfinder/userfiles/files/bugatalagizofinakol.pdf In PDF document text
    • http://clinivetmadonnadirosa.eu/userfiles/files/nezirowazip.pdfIn PDF document text
    • https://muguet.fr/sites/default/files/file/59930632224.pdfIn PDF document text
    • http://teaterskolen-efteruddannelsen.dk/ckfinder/userfiles/files/walozagixo.pdfIn PDF document text
    • http://thanhlamresort.vn/wp-content/plugins/formcraft/file-upload/server/content/files/16152e958598d5---goraseruserod.pdfIn PDF document text
    • https://fullprotec.com/ckfinder/userfiles/files/jaxuximevinufururo.pdfIn PDF document text
    • https://atx-stroy.ru/wp-content/plugins/super-forms/uploads/php/files/a4b871afddcc18412715d461e1888247/94954741835.pdfIn PDF document text
    • http://camel-republic.com/media/userfiles/files/nowifaforawolan.pdfIn PDF document text
    • http://xn--80aamwn.xn--p1ai/userfiles/file/juxobetumelunis.pdfIn PDF document text
    • http://kolkandkolkdesign.com/site/data/ws/files/jipofuvedew.pdfIn PDF document text
    • http://vncdata.net/app/webroot/uploads/files/suwug.pdfIn PDF document text
    • https://fertilizergranulatorprice.com/d/files/papevemukasipedodokifu.pdfIn PDF document text
    • http://kitpaisal.com/mypicture/file/medelowubuginirotomilor.pdfIn PDF document text
    • http://sqc.jp/user_data/editor/ckfinder/core/connector/php/upload/files/91261231235.pdfIn PDF document text
    • https://swaarm.de/app/webroot/upload/files/fovetajelidarerejimolobep.pdfIn PDF document text
    • https://www.auditek.fr/wp-content/plugins/formcraft/file-upload/server/content/files/16143010242133---veparapexudepajizunasowu.pdfIn PDF document text
    • http://garage-ys.info/js/upload/files/18263500772.pdfIn PDF document text
    • https://heritagelogs.com/wp-content/plugins/super-forms/uploads/php/files/c70euvvcs1lf45ls47f77a7m31/72152764014.pdfIn PDF document text
    • http://kommunikator.nu/demo/userfiles/file///29803171854.pdfIn PDF document text
    • http://beiwendq.com/data/attachment/file/pizemiramumulatofodana.pdfIn PDF document text
    • https://remoteyourstaff.com/calisma2/files/uploads/tiwatexokobulezatuveze.pdfIn PDF document text
    • https://baconbites.com/wp-content/plugins/super-forms/uploads/php/files/s65oaq9i1g319b6b0pr084utm0/wudat.pdfIn PDF document text
    • http://www.thelawchamber.com/wp-content/plugins/formcraft/file-upload/server/content/files/16150385605d39---31030085548.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/zMnd8XtcwSM/uplcv?utm_term=descargar+looney+tunes+para+androidPDF 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_off0000c152.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC152 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d969.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD969 10904 bytes
SHA-256: 60c56c8b0c600f44bb30234447db00509e61e5ee17280832758ce10438ed970f
font_02_sfnt_off0000f298.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF298 19420 bytes
SHA-256: 15f0b33aecd98603cd4c3a17530d634ea33e4fd68f1461976078de48f16e3723