Malicious PDF — malware analysis report

Static analysis result for SHA-256 1d19df827fdf96d1…

MALICIOUS

PDF

68.1 KB Created: 2021-10-09 08:49:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 510bf9883c25e3b79c66b8b86019797c SHA-1: 1ccdfcb005714fbe46c251ac493ca23925e98439 SHA-256: 1d19df827fdf96d1b82630d7dac8183265f5aeb558f5153a423cf2464cc3ee90
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript, a common technique for executing malicious code within documents. Heuristics indicate the JavaScript likely redirects to a link farm hosted on compromised WordPress uploads and other disposable domains, suggesting a phishing or malware distribution campaign. The ClamAV detection and ML classifier strongly support the malicious nature of this file.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9957

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://blueleaves.ru/userfiles/file/72436265226.pdf In PDF document text
    • http://hanauhrova.cz/files/19116846603.pdfIn PDF document text
    • http://chaodontuonglai.vn/uploads/ck_upload/files/40690109792.pdfIn PDF document text
    • http://blackivy.pl/userfiles/file/17731377552.pdfIn PDF document text
    • https://formapolis.it/wp-content/plugins/super-forms/uploads/php/files/86c3df593c8616d996cb5362811fed15/nufenukexusibusulijelusem.pdfIn PDF document text
    • http://thuannam.com/image/files/zotewe.pdfIn PDF document text
    • http://neogmbh.de/www/sites/default/files/userfiles/file/xavilunewuw.pdfIn PDF document text
    • http://savemaxint.com/files/file/soburubeles.pdfIn PDF document text
    • http://www.sainteuphrasia.com/www/js/ckfinder/userfiles/files/rivogato.pdfIn PDF document text
    • https://agriplan-rs.com/dados/ckfinder/files/7901421706.pdfIn PDF document text
    • http://cayxaotamphan.net/userfiles/image/file/wuwani.pdfIn PDF document text
    • https://masterok-kovka.ru/wp-content/plugins/super-forms/uploads/php/files/de8b8eb543649fe2b744a7a1495503de/kozamul.pdfIn PDF document text
    • http://fishtech.org/uploads/userfiles/file/file/zuzujupug.pdfIn PDF document text
    • https://apsco.ly/userfiles/files/votuxifejaleposogegemuba.pdfIn PDF document text
    • http://saatgaamkansarasamaj.com/admin/uploads/files/6383035660.pdfIn PDF document text
    • http://ticaproduce.com/ckfinder/userfiles/files/veboxuvo.pdfIn PDF document text
    • https://durimawar.com/contents/files/semuzalewinomaz.pdfIn PDF document text
    • https://akdenizokullari.k12.tr/wp-content/plugins/super-forms/uploads/php/files/79da5cff98893u1t572e8gn9tv/60672889135.pdfIn PDF document text
    • https://threadworx.com/thread/admin/uploads/file/78913615439.pdfIn PDF document text
    • https://bike-accessories.supersites.gr/content/ckfinder/files/88980890438.pdfIn PDF document text
    • http://www.next-conseil.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1615ddcf5191eb---51557498737.pdfIn PDF document text
    • https://pvcmikser.com/upload/files/30794714683.pdfIn PDF document text
    • https://daqing-jewelry.com/uploads/files/202110082043265093.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3vuEKuznOb8/uplcv?utm_term=white+rice+pilafPDF 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_off0000af23.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAF23 10176 bytes
SHA-256: 635f91515253edbc1a0259a00d444d83ea88742d965b17cd0a1aef71198f0d59
font_01_sfnt_off0000c60c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC60C 14968 bytes
SHA-256: cab1178aecd53e9ce9335b24303dc5240a63f6383c0e9dce30586ca061752e51
font_02_sfnt_off0000eb3b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEB3B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1