Malicious PDF — malware analysis report

Static analysis result for SHA-256 ca4f36eaa6999227…

MALICIOUS

PDF

69.8 KB Created: 2021-09-25 18:17:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 5142cb828c3bf40d9555d8433a0239bf SHA-1: 53ac189ef3fc451c78ecfe6b23d109e00f6c7da6 SHA-256: ca4f36eaa699922773b3956341831691286548a8dcaa7c80d94558dfcae11c64
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a phishing or malware distribution attempt. It functions as a link farm, containing numerous URLs that point to potentially compromised websites or disposable hosting. The presence of external URIs and link farm heuristics strongly suggests an intent to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

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://coretry.ru/uplcv?utm_term=clicker+heroes+unblocked PDF link annotation
    • http://bienbao.org/uploads/files/gosamanukuzojalokulov.pdfIn PDF document text
    • http://fitviewer.biz/files/file/91242730119.pdfIn PDF document text
    • https://petrovsky14.ru/docs/files/88239652615.pdfIn PDF document text
    • https://trucraftsmanship.com/wp-content/plugins/formcraft/file-upload/server/content/files/16136727a33a48---nozes.pdfIn PDF document text
    • http://hoachathoanggia.com/userfiles/file/bejiwisasanopumuwibavi.pdfIn PDF document text
    • http://hansungidschool.com/userfiles/file/75100654904.pdfIn PDF document text
    • http://depcip.com/app/views/panel/ckfinder/userfiles/files/26251087451.pdfIn PDF document text
    • http://arqing.es/ckfinder/userfiles/files/1679343532.pdfIn PDF document text
    • https://monyetjoget.com/contents/files/5355350304.pdfIn PDF document text
    • http://www.canadiantreasurer.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614c1b9b4741c---18394316720.pdfIn PDF document text
    • https://ashasuchikala.com/ckfinder/userfiles/files/3603742551.pdfIn PDF document text
    • https://totalsewa.com/userfiles/file/beniwural.pdfIn PDF document text
    • https://hiroyoung.com/data/files/sededizakinanusufimu.pdfIn PDF document text
    • https://castel.ro/userfiles/file/95321941073.pdfIn PDF document text
    • http://xinghui.co/upload/ckimg/files/202109212131195910.pdfIn PDF document text
    • http://babywagen24.de/userfiles/file/6342476546.pdfIn PDF document text
    • https://delcinfo.ru/img/files/files/30043092350.pdfIn PDF document text
    • http://rbc-bezorgdiensten.nl/upload/65872562637.pdfIn PDF document text
    • http://lavera.it/wp-content/plugins/formcraft/file-upload/server/content/files/1614492f815c16---21052318528.pdfIn PDF document text
    • http://fiumaradelsossio.it/userfiles/files/manevazunesokoraxupabika.pdfIn PDF document text
    • http://www.homefacelifters.com/wp-content/plugins/super-forms/uploads/php/files/2af0f1ad63f9d3b9a790e55952e8390b/vofuzibunikaferekuz.pdfIn PDF document text
    • https://kakvkusno26.ru/wp-content/plugins/super-forms/uploads/php/files/e569813510a273846f7981ce5ddfd506/69209019558.pdfIn PDF document text
    • http://www.investing-in-women.com/wp-content/plugins/formcraft/file-upload/server/content/files/16149529426613---91051554801.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_off0000b009.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB009 16004 bytes
SHA-256: 48188cc39f4039b2abcc57be764e31a8ccb6bc9c2b851f9a12c798f33b72f4e9
font_01_sfnt_off0000d7e0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD7E0 10572 bytes
SHA-256: d479807c7c18550b596e723138abaf30256811832b9d44ec33850425f071cd67
font_02_sfnt_off0000efe3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEFE3 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1