Malicious PDF — malware analysis report

Static analysis result for SHA-256 78202844575c3d37…

MALICIOUS

PDF

75.5 KB Created: 2021-03-25 03:06:16 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-20
MD5: 136b8b9a23107123432df36c7ff78bea SHA-1: 23ae9fc675f752ae548e3933a837dde55aebd38f SHA-256: 78202844575c3d37f0cc930547168bea174b2b8fc9a4fb5a790a3f7b67ed9834
126 Risk Score

Malware Insights

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

The sample is a PDF file flagged by ClamAV as Pdf.Phishing.Trojan and by an ML classifier as malicious. It contains numerous embedded URLs, with one heuristic specifically identifying it as a link farm on disposable hosting. While no executable scripts were extracted, the presence of many external links suggests an attempt to redirect users to malicious sites, likely for phishing or to download further payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9993

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://druttle.ru/wix?keyword=teaching+bass+clef+worksheets PDF link annotation
    • https://static.s123-cdn-static.com/uploads/4475215/normal_5fefec7f41d82.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4367640/normal_6059e21f01fa8.pdfIn PDF document text
    • http://kokulotasuz.mygamesonline.org/couple_compatibility_test.pdfIn PDF document text
    • http://fedexonep.mypressonline.com/common_accounting_interview_questions_and_answers.pdfIn PDF document text
    • http://gojovujewinunuj.mygamesonline.org/devops_handbook_3_ways.pdfIn PDF document text
    • http://baxusajatos.sportsontheweb.net/givogotidodit.pdfIn PDF document text
    • http://kawasus.scienceontheweb.net/what_is_perception_of_color.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4382948/normal_602e81e74cf0f.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4481072/normal_5ff8aa7b668fa.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4404285/normal_603ef39627182.pdfIn PDF document text
    • http://kuworekokinig.medianewsonline.com/78985680998.pdfIn PDF document text
    • http://sifaritube.sportsontheweb.net/busujaladukewubad.pdfIn PDF document text
    • http://jinobuzid.scienceontheweb.net/sed_and_awk_programming.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://uploads.strikinglycdn.com/files/686db6ab-6315-48e4-aa34-cc8e9caf573c/federal_rules_of_civil_procedure_rules_and_commentary_2020_ed.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/74d7cb71-4159-4ebd-a934-22b2edac99aa/how_to_identify_rhythm_in_a_poem.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/5663b1bc-7665-4368-afd0-fccb4aaf2035/kugoraxemakikepapamewekuv.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/13c1b4f1-1538-437a-b4f6-f68a4cfbf1c9/how_to_write_a_letter_to_remove_a_board_member.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/54be80b7-748a-49f1-a365-76d3b374c037/nolutiparotilurovopajar.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/24943455-52f6-462d-872f-dd5ab7e0f67d/machine_sound_effect_soundbible.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/7e979141-fdbc-4b6a-a758-c17104c655ea/29012024881.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/1a8485cc-254d-4470-a166-5c24694d82cf/jupofo.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/4bd6a72a-3d8f-42ec-b19b-c2a7ade40093/excel_vba_message_box_input_date.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/3838d6f5-4edf-4297-8669-86958101adca/70092929421.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 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e9b5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE9B5 5388 bytes
SHA-256: e4bbbedce42b4a82c6d9f729889bb868d5810c87de4bb18ad26298fce7199546
font_01_sfnt_off0000fc13.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFC13 10732 bytes
SHA-256: e6bc0d0e18762a9dc0f80889777c838a8f5d18e1de800818f19d870cc4da26a0