Malicious PDF — malware analysis report

Static analysis result for SHA-256 d819af94ca8525cd…

MALICIOUS

PDF

81.3 KB Created: 2021-09-06 02:26:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 3a689d5bb22e82c991e6675ad313c2fe SHA-1: d6ca5c59ab76ba44ef533f4357d552f1bdaae4fd SHA-256: d819af94ca8525cd4575bbfa4ff39b5ae2a0c7edb6403bec652601c20e74454e
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised CMS upload directories or are part of a link farm hosted on disposable domains. ClamAV detected this file as Pdf.Phishing.Trojan, and the ML classifier also flagged it as malicious. The primary attack pattern appears to be directing users to malicious content through a series of redirects and compromised sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9960

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 http://kirakuramen.com/uploads/files/lonirujijuri.pdf
    • http://trufeel.com/ckeditor/ckfinder/uploadfile/files/92062596465.pdf
    • http://pcccphucvinh.com/upload/files/12730348658.pdf
    • http://constructionone.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160ae8a83d3de3---bezorizijadijibu.pdf
    • https://www.rowtheerne.com/wp-content/plugins/super-forms/uploads/php/files/9bf1b819c7123a8cbd3c2689ccd902c4/gijuluwarorelugelafikifap.pdf
    • http://maxgear.cz/webpagebuilder/ckfinder/userfiles/files/6037626622.pdf
    • http://thefutureofgolf.eu/wp-content/plugins/formcraft/file-upload/server/content/files/16113ed8e38c1f---lumipilajurufusake.pdf
    • https://www.almuhja.com/ckfinder/userfiles/files/dutapume.pdf
    • https://rajatotogroup2.com/contents//files/xemexitukuwuzujef.pdf
    • http://chiari-web.com/ckfinder/optimist/files/sivijubowogejomojirevoda.pdf
    • http://morard-mcf.fr/data/Files/vadapelog.pdf
    • https://cffcommunications.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1/16093da30598e9---zowuviweruwutubavidu.pdf
    • http://eca.or.th/ckfinder/userfiles/files/398129027.pdf
    • http://alteredcompta.com/buddha/ckfinder/userfiles/files/vepidinejibujaxig.pdf
    • https://mmgrowersg.com/ckfinder/userfiles/files/79151774804.pdf
    • https://vizzzio.ru/wp-content/plugins/super-forms/uploads/php/files/bbf53af3bd1d1051fac5477fb2553f66/pagakaruremiruwozegame.pdf
    • http://ahcxdq.com/uploads/file/110855158156.pdf
    • https://nhaban24h.com.vn/wp-content/plugins/super-forms/uploads/php/files/ntd1b5mmnnj5r223tn0kftapi0/wudumekurifutitexugixu.pdf
    • http://www.klccpa.com/userfiles/file/
    • https://regenerativetherapyforpain.com/wp-content/plugins/super-forms/uploads/php/files/6d0d7de7ada4aef814753873d619cf1d/topigupuzoredikuz.pdf
    • https://yaslibakicisi.net/userfiles/file/womuv.pdf
    • https://lightingsystemscol.com/wp-content/plugins/super-forms/uploads/php/files/fac658e20cbde9eba08d82fba42b06e3/96578514833.pdf
    • https://krimgranit.ru/wp-content/plugins/super-forms/uploads/php/files/e7483f83ed8d265cbb96f64c263b2c9f/40529123846.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/DOqCt-cVA4I/uplcv?utm_term=ejercicios+resueltos+de+la+tercera+ley+de+la+termodinamica+pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d4d6.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xD4D6 16792 bytes
font_01_sfnt_off0000ece8.bin
7331495f0091914d22b13e332e161c9445d2e5c21f2382b948c2a5f3ab35a735
pdf-font-stream PDF embedded font (sfnt) at offset 0xECE8 18832 bytes
font_02_sfnt_off00011cfe.bin
b4e0b37bde6440ac234bc6939fc07e03337650c073c9693fa3a161f327e885d9
pdf-font-stream PDF embedded font (sfnt) at offset 0x11CFE 11108 bytes