Malicious PDF — malware analysis report

Static analysis result for SHA-256 8fcb65fc30ced879…

MALICIOUS

PDF

101.4 KB Created: 2021-05-21 11:50:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-07-13
MD5: 5914555a8e9961129c967692f72c1ebe SHA-1: 417645fbb42a97092550584dfef3528db2dd0f55 SHA-256: 8fcb65fc30ced879aa51ec24b6179bc4a23e9c5fd8f42d77212e2ec5d8f1d575
186 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many hosted on disposable domains, indicating a link farm designed to direct users to potentially malicious content. The ClamAV detection and ML classifier strongly suggest malicious intent, likely for phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and numerous external URLs point towards a common tactic of redirecting users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9993

Heuristics 6

  • 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 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://jumiwimov.ru/strik?utm_term=armenian+alphabet+exercises PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4383703/normal_6031d6f899d9b.pdfIn PDF document text
    • https://wuxinaruniluxod.weebly.com/uploads/1/3/4/8/134882591/vedozinudoweteraf.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4470035/normal_605a597e2e7da.pdfIn PDF document text
    • https://vuxulirupam.weebly.com/uploads/1/3/5/3/135346280/477551.pdfIn PDF document text
    • https://finukapaxareb.weebly.com/uploads/1/3/4/4/134494590/xosinevovonab-bikigisijaro-lomanoribefu.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4371013/normal_6031ac6ccf6c9.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4409627/normal_5fe3ad31a85a5.pdfIn PDF document text
    • https://zizozuku.weebly.com/uploads/1/3/4/7/134732263/doxefipo.pdfIn PDF document text
    • https://majivuwuwu.weebly.com/uploads/1/3/2/6/132683475/fipuzawalufutasu.pdfIn PDF document text
    • https://dapalijika.weebly.com/uploads/1/3/0/7/130738969/9845058.pdfIn PDF document text
    • https://jaxevilin.weebly.com/uploads/1/3/1/6/131606955/votukukozupa.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4390097/normal_606b739327f85.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/lunojol/bedroom_dresser_drawer_guides.pdfIn PDF document text
    • https://s3.amazonaws.com/nagudo/xalosijimetaxunewet.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/87cb2c57-4079-4049-b6fe-3db7448a4d93/tadapojik.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/93b32a04-cdfa-40f4-8bcb-6cda92b28a0e/processing_bisectors_of_an_angle_worksheet_answers.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/c315e03a-af4d-4d92-bae3-d0e37cda26fb/20944445371.pdfIn PDF document text
    • https://s3.amazonaws.com/rimepusox/number_theory_examples_questions_answers.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/a1c3e3f6-84f6-4c12-8b30-34a4c31e67c4/el_pollo_loco_offers.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/c4b5f6f3-0e3a-4136-8881-22e3f593a451/crossbow_plans_uk.pdfIn PDF document text
    • https://s3.amazonaws.com/resabomibogodaw/addition_subtraction_multiplication_worksheets_grade_3.pdfIn PDF document text
    • https://s3.amazonaws.com/xupizewuxere/adobe_premiere_crashing_on_startup.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_off000133bb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x133BB 5372 bytes
SHA-256: f413b712231f9739ad0732c266b089f8f07167d4fb520d2d9183257207cc2d19
font_01_sfnt_off000145c6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x145C6 10904 bytes
SHA-256: 607f1937cf09e3caeaa761966793fc4add296ddaac75574f5e45683017ba0876
font_02_sfnt_off00016ae0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x16AE0 18736 bytes
SHA-256: 86d7a08401cb6428b3a9761393ac46c39c437f61e414c0a106b86911f3c13452