Malicious PDF — malware analysis report

Static analysis result for SHA-256 3386969157e11311…

MALICIOUS

PDF

84.5 KB Created: 2021-09-08 09:59:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: fed4470bf40440a4e497030b997f356a SHA-1: 084c836ce34f438c59c96468ec6b4d75db20953f SHA-256: 3386969157e113114e60cfa19c5058c0f96857aad7e4961802bf20fa4989be04
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains numerous embedded URLs, many of which point to compromised websites or link farms, indicating a phishing or redirection attempt. The ClamAV detection and ML classifier strongly suggest malicious intent, likely to lure users to malicious sites. The document body is heavily obfuscated and appears to be generated by wkhtmltopdf, not containing user-readable content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9860

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://cructi.ru/uplcv?utm_term=short+stories+for+children+pdf PDF link annotation
    • https://inlandautorepairmurrietaca.com/wp-content/plugins/super-forms/uploads/php/files/5138c9a967dcf152122eeaa15847cadd/ginajipunusugarufum.pdfIn PDF document text
    • https://bya-ingenieria.com/ckfinder/userfiles/files/26725777576.pdfIn PDF document text
    • https://geneticapanama.com/userfiles/file/65761953880.pdfIn PDF document text
    • http://tz5168.com/uploadfile/image/2021/05/20/file/20210520_202231_117.pdfIn PDF document text
    • https://petrovsky14.ru/docs/files/rafajabavewamewilejofu.pdfIn PDF document text
    • https://www.hasmow.com.au/application/third_party/ckfinder/userfiles/files/18727024143.pdfIn PDF document text
    • http://gzky.cn/dubeite/ckfinder/userfiles/files/20210826_121909.pdfIn PDF document text
    • http://premium-t.info/files/files/72091793512.pdfIn PDF document text
    • https://www.hungryalex.com/wp-content/plugins/super-forms/uploads/php/files/ec82kfkdk3ktpjtvfth8hdbfs2/98540272264.pdfIn PDF document text
    • https://total-sport.pl/img/upload/files/42244354665.pdfIn PDF document text
    • https://stradatextiles.com/upload/ckfinder/files/80590566624.pdfIn PDF document text
    • http://www.leesii.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608cd5d1ed4fc---sezividelajikafe.pdfIn PDF document text
    • http://ngocminhcnc.com/demo_thietbimay_24_7/upload/files/kikulej.pdfIn PDF document text
    • http://pkynfe.net/userfiles/file/xadezekutesefixezuja.pdfIn PDF document text
    • http://www.taylormadetc.com/siteadmin/ckfinder/userfiles/files/vujerenigiz.pdfIn PDF document text
    • http://vinag7furniture.com/app/webroot/files/editor_upload/files/dabuvivu.pdfIn PDF document text
    • http://geo-equipe.it/userfiles/files/81335481104.pdfIn PDF document text
    • http://www.gdchgs.com/admin/img/files/gafupowevojaxesabil.pdfIn PDF document text
    • https://hoffmanowska.pl/wp-content/plugins/formcraft/file-upload/server/content/files/160e5cc32a9093---xumivoluzo.pdfIn PDF document text
    • https://kvartira-zalog.ru/wp-content/plugins/super-forms/uploads/php/files/945ff9a32c2d9835c032e25fe7c8c534/robalorafafukos.pdfIn PDF document text
    • http://kaies.net/upfiles/210726092036170717jrkjb0.pdfIn PDF document text
    • https://www.cfo-search.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607f5137321c2---56903678867.pdfIn PDF document text
    • http://smartcookieacademy.com/wp-content/plugins/formcraft/file-upload/server/content/files/16088963921a9a---51594384520.pdfIn PDF document text
    • http://infinity-pro.ru/userfiles/file/wenamexolasekemamafiw.pdfIn PDF document text
    • https://kingdomdatesuae.com/userfiles/files/64381655010.pdfIn PDF document text
    • http://villaturri.it/wp-content/plugins/formcraft/file-upload/server/content/files/160edaa8529caf---magajewamon.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_off0000e660.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE660 10632 bytes
SHA-256: 922c345dcde402187de5782902f28b33aeb4eb312359f4c87d63c080d3832576
font_01_sfnt_off0000fe94.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFE94 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000116a6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x116A6 18084 bytes
SHA-256: 31720eb448c6a51121c3d0068c276eae634ac2319af5d2600ce77a3786451e64