Malicious PDF — malware analysis report

Static analysis result for SHA-256 d6f8657b42786e7c…

MALICIOUS

PDF

87.4 KB Created: 2021-09-01 01:56:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: eae94985db3437817ae8f05b3453bac8 SHA-1: 516b847bcd41478c89fa795c6595c37ef255740e SHA-256: d6f8657b42786e7caca6c914f5b361e0ca32af2a3a78d454d640a70f9b9588e6
164 Risk Score

Malware Insights

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

The PDF file contains numerous embedded URLs pointing to various websites, many of which appear to be compromised WordPress installations used for hosting PDF files. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates a link farm structure, suggesting the document's primary purpose is to redirect users to external sites. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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.
  • Urgency / deadline lure low SE_URGENCY_LURE
    Document contains urgency or deadline language ('account will be terminated', 'action required within 24 hours', etc.) — useful context, but low-signal without other findings
  • 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://queure.ru/uplcv?utm_term=mcq+questions+for+class+11+chemistry+with+answers PDF link annotation
    • https://psychotherapie-dr-albrecht.de/wp-content/plugins/formcraft/file-upload/server/content/files/160787c4176d4d---27678768583.pdfIn PDF document text
    • https://action-roofing.com/wp-content/plugins/super-forms/uploads/php/files/0f3087576a6e85b59aa1cc589bf2bc76/30692761514.pdfIn PDF document text
    • https://www.marvistasales.com/wp-content/plugins/super-forms/uploads/php/files/e625308efae3ddb23d91f3bc2f469b15/waxederejokenakive.pdfIn PDF document text
    • http://mkconline.com/landmark/ckfinder/userfiles/files/84133476011.pdfIn PDF document text
    • http://studioagm.it/userfiles/files/3625050513.pdfIn PDF document text
    • http://huerural.com/uploads/image/files/semaxelalepuzozazemu.pdfIn PDF document text
    • http://przedszkolenisko.pl/userfiles/file/36985081256.pdfIn PDF document text
    • http://www.northeastmarquees.com/wp-content/plugins/super-forms/uploads/php/files/e7589c6fb962769b660b2e51f63cbbb7/76571718744.pdfIn PDF document text
    • https://mattweidnerlaw.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607ad8dfc8a9a---sobupetezakol.pdfIn PDF document text
    • https://urbanlivin.lu/userfiles/files/takonolonosafisojuwerom.pdfIn PDF document text
    • https://nam.it/wp-content/plugins/formcraft/file-upload/server/content/files/1606d54aa78d81---69487087023.pdfIn PDF document text
    • https://binarbaid.com/public_html/userfiles/file/kumakipaxatenodogekum.pdfIn PDF document text
    • https://www.rockandroll.blog.br/wp-content/plugins/super-forms/uploads/php/files/pv4kjfnnsb6u7cfu3lpue5qddr/26376527409.pdfIn PDF document text
    • https://xlux.vn/wp-content/plugins/super-forms/uploads/php/files/ruija4ov1ig2nvobi42h2787td/31737983828.pdfIn PDF document text
    • http://srmhomes.com/images/bulk_images/files/85863100918.pdfIn PDF document text
    • https://readxyz.com/wp-content/plugins/super-forms/uploads/php/files/317b639bdbaa024c452e504acf3f8247/60988015351.pdfIn PDF document text
    • https://ibeguiristain.com/userfiles/files/jesigazose.pdfIn PDF document text
    • http://marleenjansen.nl/images/uploadfiles/50934821797.pdfIn PDF document text
    • https://tmtteks.com/files/liribovu.pdfIn PDF document text
    • https://romalasergroup.com/userfiles/files/99141101642.pdfIn PDF document text
    • https://www.hotwaterfactory.com.au/wp-content/plugins/super-forms/uploads/php/files/8a9fc0397e35a1defa168f8d321fd761/vetapuwisesirudif.pdfIn PDF document text
    • http://www.radioemka.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c1090ee6d36---63422481078.pdfIn PDF document text
    • https://dianthusindustrial.com/resimler/files/xolenujux.pdfIn PDF document text
    • http://1-champagne.com/blog_images/blog_/file/69440539411.pdfIn PDF document text
    • http://www.laterveer-biesenbeek.nl/ckfinder/userfiles/files/sedexefafalebubiwufo.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_off0000eeb6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEEB6 17872 bytes
SHA-256: d605d38cc4cebc91419a399523c061d4ac7ee67b57cada91e91288d3f7c3be91
font_01_sfnt_off00011d63.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11D63 11092 bytes
SHA-256: b10198a9ce225a19b9c0b59b22ff10b024cb3399bbdcc6c3cd0fdeed85b2ddb3
font_02_sfnt_off0001373d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1373D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1