Malicious PDF — malware analysis report

Static analysis result for SHA-256 68356bdff52a7411…

MALICIOUS

PDF

84.2 KB Created: 2021-09-11 01:10:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 74c2901eef6fff415c7bdc7ddc5a3ec1 SHA-1: 8acbc43cc19b7976c008d507c49e0d009fd1ef03 SHA-256: 68356bdff52a74113f5d39b67c32cdcfb0b32addf724cb36121816ee5e465233
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by ClamAV as 'Pdf.Phishing.Trojan' and a machine learning classifier indicated a high probability of maliciousness. Heuristics identified the document as a link farm, with numerous URLs pointing to potentially compromised CMS upload storage and disposable hosting. The presence of embedded URLs and the overall structure suggest an attempt to redirect users to malicious sites for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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://crewmak.ru/uplcv?utm_term=hack+dias+ml PDF link annotation
    • https://rux-thai.com/ckfinder/userfiles/files/logogerevofiwajuf.pdfIn PDF document text
    • http://dlshixiang.com.cn/ckfinder/userfiles/files/mamawupaw.pdfIn PDF document text
    • http://baracenter.be/userfiles/file/ginanuvurofuvafe.pdfIn PDF document text
    • https://illustrations.noche.fr/images/files/93537139982.pdfIn PDF document text
    • http://kemmurad.com/webroot/img/files/70184870520.pdfIn PDF document text
    • http://lncxjzxxw.com/upload_fck/file/2021-9-9/20210909001432924586.pdfIn PDF document text
    • http://joy05.com/_UploadFile/Images/file/71453329671.pdfIn PDF document text
    • https://www.elektrobetrieb-scholz.de/wp-content/plugins/formcraft/file-upload/server/content/files/16135932febf5a---5516845875.pdfIn PDF document text
    • http://epilia.com/upload/FCKEditorfile/pakuninerijisuzizewugo.pdfIn PDF document text
    • https://www.golaw.net/wp-content/plugins/formcraft/file-upload/server/content/files/16133dedf19744---wevuwexawidumujapexow.pdfIn PDF document text
    • http://skupka54.ru/upload/m/58422556105.pdfIn PDF document text
    • http://kccmaul.com/files/files/rebezenekukini.pdfIn PDF document text
    • http://constructionone.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1613aabce96fa8---vobumo.pdfIn PDF document text
    • http://www.barbazan-debat.fr/ckfinder/userfiles/files/pobevamekipikuriwirara.pdfIn PDF document text
    • https://hotelexpert.ro/uploads/files/pabaz.pdfIn PDF document text
    • https://fedico.ca/upload/editor/file/71487036817.pdfIn PDF document text
    • http://gaziogluenerji.com/images_upload/files/muzixulurudevopefop.pdfIn PDF document text
    • http://1utilaje.ro/mm/file/90539820894.pdfIn PDF document text
    • http://danguykhoidoanhnghiephp.vn/Upload/files/64245952135.pdfIn PDF document text
    • https://ises.ca/phpsites/vertical_living/uploads/file/36845880654.pdfIn PDF document text
    • http://szolnokepul.hu/userfiles/file/diwikafezarupo.pdfIn PDF document text
    • https://podereilmontaleo.it/writable/public/userfiles/file/726027544.pdfIn PDF document text
    • http://uptownchantilly.com/uploads/files/45966617721.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_off0000e700.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE700 17868 bytes
SHA-256: df24224f6fac372c9814bb2032500bb9c18cf75b56ac9c6f5020554d8354d5dd
font_01_sfnt_off0001153d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1153D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012d54.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12D54 10060 bytes
SHA-256: f7d87ab5927ffaac740166112c743916e4ab567dd9ecee4f4c18b0021a8f85bc