Malicious PDF — malware analysis report

Static analysis result for SHA-256 81b73cd60441fe55…

MALICIOUS

PDF

67.0 KB Created: 2021-02-25 20:42:08 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-05-26
MD5: 34572ddf65ce51e59d0736796bd2fa8a SHA-1: 4ce809bef4ac3785f82ac193fb55dfa59ba78051 SHA-256: 81b73cd60441fe557cd82226dc711fc477598fde10e0b41c54a725d653fadcf7
186 Risk Score

Malware Insights

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

The PDF contains numerous external links, many pointing to disposable domains and Weebly-hosted PDFs, suggesting a link farm for SEO spam or phishing. The ML classifier and ClamAV detection strongly indicate malicious intent. While no scripts were explicitly extracted, the PDF structure and embedded URLs are indicative of a malicious document designed to redirect users to potentially harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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
  • Small PDF contains mass external PDF link farm critical PDF_SEO_LINK_FARM
    Small PDF contains many clickable external PDF links, mostly clustered on one host. This matches generated SEO/link-farm PDF carriers used to route users into malicious or unwanted-software delivery chains, rather than a normal document citation pattern.
  • 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://jottigo.ru/wix?keyword=letter+from+birmingham+jail+assessment+answers PDF link annotation
    • https://static.s123-cdn-static.com/uploads/4392237/normal_5ff86a704807a.pdfIn PDF document text
    • https://bakurisevujukuj.weebly.com/uploads/1/3/4/3/134368754/tufetiwomi.pdfIn PDF document text
    • https://piworanup.weebly.com/uploads/1/3/2/6/132681558/zadijutavapale.pdfIn PDF document text
    • https://mefufexuwi.weebly.com/uploads/1/3/4/0/134019004/jofirosagoluke.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4465402/normal_60037bb300991.pdfIn PDF document text
    • https://kutemipemowu.weebly.com/uploads/1/3/4/8/134860595/2381836.pdfIn PDF document text
    • http://aycotoro0.xyz/competitive_exams_questions_and_answers_in_kannada3ahu6.pdfIn PDF document text
    • https://bimozasobo.weebly.com/uploads/1/3/1/3/131398313/865419.pdfIn PDF document text
    • https://gokaxavel.weebly.com/uploads/1/3/5/3/135316782/9147041.pdfIn PDF document text
    • http://surisetufuna.iblogger.org/28162240527.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • https://s3.amazonaws.com/wozoxub/27559946400.pdfIn PDF document text
    • https://s3.amazonaws.com/kitakilesa/71110333330.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

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000be31.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBE31 5216 bytes
SHA-256: 68ad05cd13848fd511ad85e5fd732df7c87e7595f70146011257277622eab8a5
font_01_sfnt_off0000cfce.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCFCE 9728 bytes
SHA-256: 09772ed3ad24ee8bdb230c0a59e7c8200d0e9ce83f95cb2ce1652d9247d6ac8e
font_02_sfnt_off0000f0ff.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF0FF 4324 bytes
SHA-256: a542ec26cea93e049a2e27cd59b1347dd9bbdea13775fd7b822b3c2b3136116f

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