Malicious PDF — malware analysis report

Static analysis result for SHA-256 11335efbab3ac11a…

MALICIOUS

PDF

70.8 KB Created: 2021-09-25 20:33:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: eea07fc84b043ecccc545549a6566772 SHA-1: bfcbb6c56c71c7692a9b03b4ea2a0878684b3e5f SHA-256: 11335efbab3ac11aef5527b4f4228f952f8b40f29606bfa79d08f5b0f3a6b0ed
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which are hosted on compromised websites or disposable domains, indicating a link farm designed to redirect users to malicious content. The ClamAV detection and ML classifier strongly suggest malicious intent, likely phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with techniques used to lure users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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=how+to+get+free+robux+2020+no+verification PDF link annotation
    • https://thokhoavietnam.com/upload/files/bumubulokijizopa.pdfIn PDF document text
    • http://iviltra.lt/images/files/11565674147.pdfIn PDF document text
    • http://secoinblock.com/upload/files/limodototojomivur.pdfIn PDF document text
    • http://waycreon.net/bhaskar/yii/upload/files/xetulopi.pdfIn PDF document text
    • http://pass38.com/images/contentimages/files/wukisi.pdfIn PDF document text
    • http://theexplorerthai.com/userfiles/files/tulejanelifojujefol.pdfIn PDF document text
    • http://ng-sons.com/userfiles/file/57721714124.pdfIn PDF document text
    • http://la-roofers.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/161409501cfb3b---tosigutuburidumugaraluwob.pdfIn PDF document text
    • http://iweldbot.com/ckfinder/pho/files/86477737877.pdfIn PDF document text
    • https://hantverksakuten.se/ckfinder/userfiles/files/fimexisebuxunoj.pdfIn PDF document text
    • http://taikenplan.jp/ckfinder/userfiles/files/mikumujafe.pdfIn PDF document text
    • https://gemwares.com/userfiles/file/xepapazuxamovo.pdfIn PDF document text
    • http://brilsports.ro/userfiles/file///72836186886.pdfIn PDF document text
    • http://escrima-rlp.de/userfiles/file/27554855727.pdfIn PDF document text
    • https://asigurareingermania.ro/wp-content/plugins/super-forms/uploads/php/files/5a4ea46soj94a3e9ovbn5m9o6n/13610534258.pdfIn PDF document text
    • http://emons-verlag.net/testarea/cwsCMSlight/media/files/najeji.pdfIn PDF document text
    • http://lidaoxc.com/upload/files/18543752492.pdfIn PDF document text
    • http://vamaconsulting.sk/userfiles/file/43876285260.pdfIn PDF document text
    • https://leicht-spb.ru/wp-content/plugins/super-forms/uploads/php/files/d079367f4bf62c26437c7219d46c9ef1/puzuzofiwex.pdfIn PDF document text
    • https://resicolor.com/upload/files/11124393501.pdfIn PDF document text
    • http://jtylek.pl/Upload/file/nexexukukanuzopa.pdfIn PDF document text
    • http://lex-ter.ru/admin/ckfinder/userfiles/files/ruwazozen.pdfIn PDF document text
    • http://lavera.it/wp-content/plugins/formcraft/file-upload/server/content/files/1614ca693d0c3f---dimipirivuwupelubod.pdfIn PDF document text
    • https://abhrian.com/userfiles/files/80960627022.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_off0000b2cd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB2CD 15984 bytes
SHA-256: 09fbf14172f9d9e937f665e61302a647899fa257f75d6b84a82be13b20c75aa3
font_01_sfnt_off0000db3f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDB3F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f356.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF356 11024 bytes
SHA-256: cfce275ec941fc6554610ad991e776651ae9a1446843a2892d783e9f64020776