Malicious PDF — malware analysis report

Static analysis result for SHA-256 a179dccca21640b3…

MALICIOUS

PDF

91.5 KB Created: 2021-07-14 05:16:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-17
MD5: 59e4c58096b6b3715a5aa373d71f11de SHA-1: 7b6727fe6cb0cd2acc71c51454554b85ecdb7244 SHA-256: a179dccca21640b3f6faeda9204fb6303910d4d696d8bd3947870f3eb0b4fb97
164 Risk Score

Malware Insights

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

The sample is a PDF containing embedded JavaScript, which is a common technique for exploiting vulnerabilities or delivering malicious content. The PDF also contains numerous external links, many pointing to compromised CMS upload directories or disposable hosting, suggesting a phishing or link-farming campaign. The ML classifier and ClamAV detection strongly indicate malicious intent, likely involving the execution of JavaScript to download and execute a second-stage payload.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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 https://nomylo.ru/uplcv?utm_term=weathering+erosion+and+deposition+definition PDF link annotation
    • https://taechoclub.com/FileData/ckfinder/files/20210613_09307E03257C6DB7.pdfIn PDF document text
    • http://www.retorika-zidar.si/ckfinder/ckeditor_uploaded_files/files/najijodaven.pdfIn PDF document text
    • http://www.yourhealthyourchoice.org/wp-content/plugins/formcraft/file-upload/server/content/files/16071effa0cc42---kurukuwovojipigevetowaro.pdfIn PDF document text
    • http://secureyun.cn/uploadfile/file///2021070714474024.pdfIn PDF document text
    • https://www.infrascale.com/wp-content/plugins/super-forms/uploads/php/files/6e4fd58a12645c9e40b201e5804160dd/54442705023.pdfIn PDF document text
    • https://www.chortho.co.uk/wp-content/plugins/super-forms/uploads/php/files/d6tvatrvlul8al3i3tsnmkdqff/giritanivasibe.pdfIn PDF document text
    • http://www.driftime.ee/wp-content/plugins/formcraft/file-upload/server/content/files/1608bedabef0f8---51634784861.pdfIn PDF document text
    • http://pizzeria-millemiglia.de/app/webroot/img/editor/file/71939077325.pdfIn PDF document text
    • http://monkey-do.net/userfiles/file/xavejogotanabakodiveribov.pdfIn PDF document text
    • http://doorsatyrau.com/ckfinder/userfiles/files/nisijatova.pdfIn PDF document text
    • http://www.olympussverige.se/wp-content/plugins/super-forms/uploads/php/files/3pjnv0drv0o8hjoamp46elra41/82472673333.pdfIn PDF document text
    • http://pwr-tech.ru/userfiles/file/14540495855.pdfIn PDF document text
    • https://christianboudreau.com/wp-content/plugins/formcraft/file-upload/server/content/files/16071cb93cfe12---56934165388.pdfIn PDF document text
    • https://terravistahometeam.com/wp-content/plugins/super-forms/uploads/php/files/22263c36e25fc6b7fa725020abfc7877/sopeketuvabivetusel.pdfIn PDF document text
    • http://2girlstrippin.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607ec1ea30e5b---dugadixe.pdfIn PDF document text
    • https://alphaveneers.co.uk/wp-content/plugins/super-forms/uploads/php/files/f6df41434ce6edb7964695c15202d549/23252821743.pdfIn PDF document text
    • https://cananalimdar.com/wp-content/plugins/super-forms/uploads/php/files/7pbt01smts3ld0smuh6vu722sq/kibujegubukutuvad.pdfIn PDF document text
    • http://burningspearmarketplace.com/js/ckfinder/userfiles/files/41711697721.pdfIn PDF document text
    • http://studioschicchi.eu/userfiles/files/zorigipu.pdfIn PDF document text
    • https://betonwerkendejonge.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160a5877390502---mugom.pdfIn PDF document text
    • https://detectiveoffice.net/userfiles/file/roxevu.pdfIn PDF document text
    • http://thegroverestaurantnj.com/userfiles/files/voxowozogem.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_off0001060b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1060B 16208 bytes
SHA-256: 4a755ea88a113ae541e8a2881b6db3d94700aa93c78f3b927bd40d8d821a2d45
font_01_sfnt_off00013017.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13017 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001482e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1482E 10724 bytes
SHA-256: 9f013dcdba0c816219d39ba83360b841f2639af2cd55e59a4773a94a36365ac3