Malicious PDF — malware analysis report

Static analysis result for SHA-256 939367871a5b10c5…

MALICIOUS

PDF

69.5 KB Created: 2021-09-24 13:12:02 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 60a117d8fb28be5e24f47c55991ec19a SHA-1: 89defb4744d9eda266bbd887f8fe48ce8718cfc2 SHA-256: 939367871a5b10c51e229a83a4d72752cb1adaabcf655bae14afac4105a20baa
156 Risk Score

Malware Insights

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

This PDF file was flagged by multiple heuristics and a machine learning classifier as malicious. It functions as a link farm, containing numerous URLs that point to external resources, some of which are hosted on compromised CMS uploads. The primary purpose appears to be directing users to potentially harmful content, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://gadesign52.com/uploads/files/202109100822577203.pdf In PDF document text
    • https://rosebankprimary.co.za/inc/ckfinder/userfiles/files/23613368943.pdfIn PDF document text
    • http://tarp.longi.tw/uploadfiles/nowupag.pdfIn PDF document text
    • http://cctsw.net/whly/up_files/FCK/file/20210912_021926_193.pdfIn PDF document text
    • http://www.sunarmisir.com.tr/wp-content/plugins/super-forms/uploads/php/files/spji0ch78q6k8sapnn57pgkt71/24304645550.pdfIn PDF document text
    • http://apex-architect.ru/images/file/98939401942.pdfIn PDF document text
    • http://ipsgroupjjn.org/userfiles/file/66964416901.pdfIn PDF document text
    • http://koreaseowon.com/ckupload/files/42779905427.pdfIn PDF document text
    • http://antwerp-rentals.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613760b9a6bc7---58361516755.pdfIn PDF document text
    • http://www.myhhsi.com/wp-content/plugins/super-forms/uploads/php/files/7df6b18ebfc3d0eea5c4a73d01357637/mevod.pdfIn PDF document text
    • http://kubkao-kubpla.com/userfiles/files/desewesu.pdfIn PDF document text
    • http://thekreativecompany.com/uploaded_files/userfiles/files/80094303653.pdfIn PDF document text
    • http://leebyunghun.kr/new/upload/board/files/55522613525.pdfIn PDF document text
    • http://art-wonders.com/ckeditor/ckfinder/core/connector/php/uploads/files/17426691071.pdfIn PDF document text
    • https://anbuadidravidarmatrimony.com/ckfinder/userfiles/files/didasegodadezesokoba.pdfIn PDF document text
    • https://sharidendesignasphalt.com/wp-content/plugins/super-forms/uploads/php/files/6e240cca54f201088d0c2242de16243e/92932037962.pdfIn PDF document text
    • https://udachi.co.th/wp-content/plugins/super-forms/uploads/php/files/9fdthqvc9vnq14r6dburgsmbt4/sajigetujusedazabar.pdfIn PDF document text
    • http://brmhn.com/userfiles/file/20210923044243_s8dlv6.pdfIn PDF document text
    • https://hotelmitrutarija.com/uploaded/files/30179161636.pdfIn PDF document text
    • https://samowar.ch/upload/file/73336589337.pdfIn PDF document text
    • http://schroniskoorzechowce.pl/ckfinder/userfiles/files/35215855900.pdfIn PDF document text
    • http://szentistvanpatika.hu/upload/file/94105328302.pdfIn PDF document text
    • http://cutskytools.com/d/files/71817860951.pdfIn PDF document text
    • http://mbfeed.vn/upload/files/toxasefexelubapel.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/PmAiG5ZyT-k/uplcv?utm_term=deezer+premium+mod+apk+downloadPDF 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_off0000afb4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAFB4 15704 bytes
SHA-256: 9b0656ebd3b41b37fe9af2c7bd95fad6dcc714f816df48a302efbfeda583ef81
font_01_sfnt_off0000d7e1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD7E1 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000eff8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEFF8 10624 bytes
SHA-256: b1069ef814a269263afebf385e6f23d453664076e138e20cfeaa7489d1c943fa