Malicious PDF — malware analysis report

Static analysis result for SHA-256 a72592d15680f75a…

MALICIOUS

PDF

77.7 KB Created: 2021-09-15 13:48:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: 141d2ce62ad3a81107e5d2fee840cb94 SHA-1: 10e1e1056627b4fff9cd5cd97ccc7d1b099b62fe SHA-256: a72592d15680f75a06dfb6815153a74e52f12553a29086785d0d2b04d0982a87
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains an embedded JavaScript stream and numerous external URIs, many of which point to compromised WordPress sites or disposable hosting, indicating a link farm designed to lure users to malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware delivery via these external links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9993

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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=patent+notes+pdf PDF link annotation
    • https://refakatci.net/userfiles/file/vedezamep.pdfIn PDF document text
    • https://maidintown.co.uk/wp-content/plugins/super-forms/uploads/php/files/99fd112a92c938a8ba7d916c72df33ac/58736696417.pdfIn PDF document text
    • https://maryamghiasi.com/images/upload/files/37913997139.pdfIn PDF document text
    • http://taiwangallant.com/uploads/files/202109140516512200.pdfIn PDF document text
    • http://computerdoki.hu/user/file/zuzefegor.pdfIn PDF document text
    • http://eko-gospodarstwo.eu/files/file/mozobiludikuletibuv.pdfIn PDF document text
    • https://tamtam.com.ua/wp-content/plugins/super-forms/uploads/php/files/50cf471254808156d3c6fd396c45a2bf/wugokexafeb.pdfIn PDF document text
    • http://colorfulmedia.de/fotki/fotki/file/mexefazusojapuxekewo.pdfIn PDF document text
    • https://rugsdirect4u.com/uploadedfiles/file/bifupo.pdfIn PDF document text
    • http://wahluenfty.com/userfiles/soxafaj.pdfIn PDF document text
    • https://ebal.ro/app/webroot/files/userfiles/files/59292847294.pdfIn PDF document text
    • http://pvvc.cz/files/73519893749.pdfIn PDF document text
    • https://dcimx.com/files/10137726354.pdfIn PDF document text
    • http://dlzhrjd.com/images/uploadfile/files/pekuxifiriz.pdfIn PDF document text
    • https://transcendenceit.com/wp-content/plugins/super-forms/uploads/php/files/8b5481aaef0b70e43ff2868da2c24280/livisovatudo.pdfIn PDF document text
    • http://thaicockstar.com/ckfinder/userfiles/files/65887531689.pdfIn PDF document text
    • http://gold-carsales.com/js/upload/files/65162247794.pdfIn PDF document text
    • http://kanchanaspa.com/ckfinder/userfiles/files/wudufibazijofafofexu.pdfIn PDF document text
    • http://retailcop.ca/files/dujemapetexor.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_off0000cf97.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCF97 16848 bytes
SHA-256: a1ddb3f3e33748aa3463b82fca19f0aedc238494c3146c89a6f0db07a6bc802f
font_01_sfnt_off0000fad7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFAD7 10256 bytes
SHA-256: 87accba2d1125edc3900ba4ad45eac0b9f769c246df2e15c22d43b81843115ca
font_02_sfnt_off0001120a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1120A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1