Malicious PDF — malware analysis report

Static analysis result for SHA-256 ac88ae1384f672cd…

MALICIOUS

PDF

100.2 KB Created: 2021-07-24 14:43:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 7f6e95a59932f82513fd7c05cf5be093 SHA-1: b66a34a4c2e1bfc1da7d5137faa6b1402ca88a89 SHA-256: ac88ae1384f672cd2b5f34b9d681f87bd6cf5fece4848f52e406aa9f16de19d9
156 Risk Score

Malware Insights

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

The PDF contains numerous links pointing to other PDFs hosted on compromised websites, indicating a link farm designed to distribute malicious content. The ClamAV detection and ML classifier strongly suggest malicious intent, likely for phishing or malware delivery. No scripts were extracted, and the document body was unreadable.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9880

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 https://www.breastcancerfoundation.in/wp-content/plugins/super-forms/uploads/php/files/d70ed257a180e0c17a7cd9b37eed0d67/kanuranakeru.pdf In PDF document text
    • http://bachova-terapia.sk/images/file/nudusupanovunavuza.pdfIn PDF document text
    • http://ambulanceservice.pl/userfiles/file/tasukavamol.pdfIn PDF document text
    • http://www.drop-lok.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ad4fd3d2d8b---vemedipiburotoxojabufosib.pdfIn PDF document text
    • http://niezapominajkowo.eu/userfiles/file/gavom.pdfIn PDF document text
    • https://action-roofing.com/wp-content/plugins/super-forms/uploads/php/files/f687574b1c9f1bf455af715d0ab6e86b/75279268373.pdfIn PDF document text
    • https://gift-edu.ru/wp-content/plugins/super-forms/uploads/php/files/6ed2bfc0bf0ee8fad5d0c751e1171ed2/49267484593.pdfIn PDF document text
    • https://pluckywize.com/wp-content/plugins/formcraft/file-upload/server/content/files/160e7aaa604326---516132455.pdfIn PDF document text
    • http://orosweb.hu/ckfinder/userfiles/files/nakiwusijegudegekomar.pdfIn PDF document text
    • https://1sis.com/wp-content/plugins/formcraft/file-upload/server/content/files/160727f94f2534---29389684136.pdfIn PDF document text
    • http://anatolianlgs.com/userfiles/file/79742010817.pdfIn PDF document text
    • http://stellarvvv.ru/ckfinder/userfiles/files/5438979218.pdfIn PDF document text
    • https://klingende-zeder.de/wp-content/plugins/formcraft/file-upload/server/content/files/160ae0eaa0c783---12044177689.pdfIn PDF document text
    • https://www.olympusnorge.no/wp-content/plugins/super-forms/uploads/php/files/9l57md1al1p90vpj4l363e4egv/fuluzewominejupivudopa.pdfIn PDF document text
    • https://limpjet.com.br/wp-content/plugins/super-forms/uploads/php/files/a829ec036d9636350cd0fcb37fd2b60a/tarafekew.pdfIn PDF document text
    • http://xn--b1ahhafccpgkb2bxo.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/d3f3e3bb59c1eb3aa861dbd92ae2ae71/19527184306.pdfIn PDF document text
    • http://www.myhhsi.com/wp-content/plugins/super-forms/uploads/php/files/cb4f816449ddd62a0f0b24de401ce499/xoworolad.pdfIn PDF document text
    • http://ippon.lv/uploads/File/nefowewijuwokudiraba.pdfIn PDF document text
    • https://butchercurnow.com/img/shop//contents/32948848026.pdfIn PDF document text
    • http://www.airportlimofortlauderdale.net/wp-content/plugins/formcraft/file-upload/server/content/files/160738aee6005a---tikukod.pdfIn PDF document text
    • http://muskogeeroughers1967.com/clients/9/98/9899c641331876fb313f08ec475a0443/File/baxokevijimibileluditurop.pdfIn PDF document text
    • https://agilitynd.com/wp-content/plugins/super-forms/uploads/php/files/873b7b4c5cefb54d67fc2a21b10d161c/47868103063.pdfIn PDF document text
    • http://meandnetworking.com/ckfinder/userfiles/files/kerizima.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a9fc51153e1---45519218804.pdfIn PDF document text
    • https://lotteppta.com/beta/assets/file/3399027145.pdfIn PDF document text
    • https://hcs1000.org/wp-content/plugins/super-forms/uploads/php/files/36dfd9d35714f2d6d5cf83254ce44cb2/76283486594.pdfIn PDF document text
    • https://duext.com/wp-content/plugins/super-forms/uploads/php/files/820f10f5ea4593156b83296105deff42/91306791423.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/PmAiG5ZyT-k/uplcv?utm_term=yates+and+goodman+probability+and+stochastic+processes+3rd+edition+pdfPDF 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_off000121bf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x121BF 17120 bytes
SHA-256: e38c76cabd14687ceefcba1d8e8a1b36114fa40402a2c83be64a62cac4aa33fe
font_01_sfnt_off00014e5f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14E5F 11476 bytes
SHA-256: a6c4b247f83b42a4725e1e378181bf40244b7f8f726a5dc397ba27ed0a7bbe2e
font_02_sfnt_off000168e6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x168E6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1