Malicious PDF — malware analysis report

Static analysis result for SHA-256 b3b521607ff8377f…

MALICIOUS

PDF

121.0 KB Created: 2021-02-03 16:46:16 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-16
MD5: f406d51049afe66a0dafde32462c6f3a SHA-1: 23b18885f79dc7abd2a34093b36dbd099f29cd0d SHA-256: b3b521607ff8377fe144a1ab120f0894a05044d62bcc6893a2691b2b2cc61e4c
126 Risk Score
Tags
free-cdn-ebook-manual-lure

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF file contains multiple embedded URLs, with a primary focus on directing users to `https://crophysi.ru/123?utm_term=convert+utm+to+lat+long+formula`. The heuristic `PDF_SEO_DISPOSABLE_LINK_FARM` indicates that the PDF is part of a link farm hosted on disposable domains, suggesting a phishing or scam attempt. ClamAV detection as `Pdf.Phishing.Trojan` further confirms malicious intent. Although no scripts were explicitly extracted, the presence of embedded URLs and the nature of the heuristics strongly suggest a phishing attack vector.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://crophysi.ru/123?utm_term=convert+utm+to+lat+long+formula PDF link annotation
    • https://cdn.sqhk.co/nutanujel/gfjgH5h/30703970075.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4462678/normal_5fe1a76f9e23a.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4367617/normal_5fcbcbad9bf46.pdfIn PDF document text
    • http://bestpriceforukraine.xyz/giwopfvf77.pdfIn PDF document text
    • https://cdn.sqhk.co/nuvexajamu/RuEMzhc/juventus_fc_news_twitter.pdfIn PDF document text
    • http://mrt-64.ru/city_car_driving_mod_apk_revdlppel4.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4530868/normal_60061332cbac1.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://s3.amazonaws.com/kopisigapub/gejijoxuwosugegunanolamef.pdfIn PDF document text
    • https://s3.amazonaws.com/bizamesuwepe/ielts_general_training_writing_topics_with_answers.pdfIn PDF document text
    • https://s3.amazonaws.com/tokit/94865247946.pdfIn PDF document text
    • http://sobakijej.rf.gd/29966313884.pdfIn PDF document text
    • http://vowaxuf.rf.gd/thunderbolt_for_battlegrounds_apk.pdfIn PDF document text
    • http://vowaxuf.rf.gd/kerefuwuj.pdfIn PDF document text
    • http://rokidibamufoduv.epizy.com/atualizar_android_lg_k10.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://scripts.sil.org/OFLIn 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_off0001846a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1846A 4876 bytes
SHA-256: 7510e496f2bf0bc83f998b475c1dd96f448762944adf6f43a133286137924728
font_01_sfnt_off000194f3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x194F3 13304 bytes
SHA-256: ceddfdbd15e1c072408751e1057c92888bdee02c3396d4471594836f0d3970bb
font_02_sfnt_off0001c17a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1C17A 16076 bytes
SHA-256: 3098f8e70b5fa629bc49fbe595ab5dc47aeded038fd462cdaec0aa5662753641

Open this report in the interactive analyzer, or submit your own file for analysis.