Malicious PDF — malware analysis report

Static analysis result for SHA-256 ef46e51221dcb32e…

MALICIOUS

PDF

75.2 KB Created: 2021-06-19 02:59:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-22
MD5: 939fb67cf707eb646293a723529853cf SHA-1: 641561e173b179ac9a5c1e3a2b28f9cfb37e9b63 SHA-256: ef46e51221dcb32ec7020ab3bb1263113cf84363419824d0f53ba0cab6099548
156 Risk Score

Malware Insights

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

This PDF file was flagged by multiple heuristics, including a critical ClamAV detection and an ML classifier, indicating malicious intent. It functions as a link farm, directing users to various compromised websites and disposable hosting domains, likely for phishing or malware distribution. The presence of numerous URLs, many hosted on compromised CMS uploads, strongly suggests a campaign to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9999

Heuristics 6

  • 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.
  • 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://northcity.rs/slike/files/nelefovaniwovepakaju.pdf In PDF document text
    • https://na-nule.ru/wp-content/plugins/super-forms/uploads/php/files/avanjjqcm5u438bbkeo1esd8e4/mafazogomakem.pdfIn PDF document text
    • http://files.ibiza-ferien.de/file/tatewenorekep.pdfIn PDF document text
    • https://www.auditek.fr/wp-content/plugins/formcraft/file-upload/server/content/files/16077a9625e6d4---32479771219.pdfIn PDF document text
    • https://qamarapps.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bc03f90670a---85783549462.pdfIn PDF document text
    • http://ytovietnam.net/ckfinder/userfiles/files/37600925432.pdfIn PDF document text
    • https://inchirieriavioane.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1607dfa341a5aa---wusozupogixexiberulo.pdfIn PDF document text
    • http://sip7.online/wp-content/plugins/super-forms/uploads/php/files/8ba620e68323b7287a3eb66dffd9b682/tatagenojukufewaxurenejef.pdfIn PDF document text
    • https://refundsrefunds.com/wp-content/plugins/formcraft/file-upload/server/content/files/160942d13058b0---22648668758.pdfIn PDF document text
    • http://projectbudapest.hu/wp-content/plugins/formcraft/file-upload/server/content/files/1607ea3d9058f4---12846328507.pdfIn PDF document text
    • https://n-zvuk.ru/upload/file/38826115817.pdfIn PDF document text
    • https://pavaniautismschools.com/wp-content/plugins/super-forms/uploads/php/files/f552ohe5itam6r71kvkg0k4ukk/25886188956.pdfIn PDF document text
    • http://saltokisport.com/uploads/files/76870163604.pdfIn PDF document text
    • https://growmytruck.com/wp-content/plugins/super-forms/uploads/php/files/978e1fb8b33a2db143e76d93accfb236/pizujelejokitul.pdfIn PDF document text
    • http://alexhoffordphotography.com/temp/files/file/99504896628.pdfIn PDF document text
    • http://lifestyleufa.ru/wp-content/plugins/super-forms/uploads/php/files/b40f8d667a9f0f44177320cc07d5ab2c/jepoj.pdfIn PDF document text
    • http://novichiha.ru/pic/file/dewaroru.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BvfzZFkJO3s/uplcv?utm_term=5+principles+of+public+relationsPDF 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e80c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE80C 5180 bytes
SHA-256: 9ef7633efe490fb2686dbc4023ecc8954f493b31ee404088c452b0ff6458ef3f
font_01_sfnt_off0000f9b8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF9B8 11268 bytes
SHA-256: 4dc1fa5633301c660fb290d2fbd2e1183df6c9bb6b071c6224f0a84d154c09c2