Malicious PDF — malware analysis report

Static analysis result for SHA-256 58c88ec06e958609…

MALICIOUS

PDF

99.8 KB Created: 2021-06-08 22:57:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-27
MD5: a86ae63fa1c8f6fdcc39aee810614354 SHA-1: 49c5b654628cd6f0cebf948d4469f66a8e5343e5 SHA-256: 58c88ec06e958609c8c1a959858a6bdf6d524f99c2b74dd881e42370f1420bcc
186 Risk Score

Malware Insights

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

The PDF file contains a large number of external links, many pointing to disposable hosting services, indicating a link farm designed to redirect users. The ClamAV detection and ML classifier strongly suggest malicious intent, likely phishing or malware distribution. While no scripts were explicitly extracted, the PDF structure and link farm behavior are indicative of techniques used to lure users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://crysiq.ru/pbw?utm_term=arm+processor+full+form PDF link annotation
    • https://rudadikisoma.weebly.com/uploads/1/3/1/6/131606677/tedubope.pdfIn PDF document text
    • https://salotoniv.weebly.com/uploads/1/3/5/3/135305201/66205.pdfIn PDF document text
    • https://tegomufowake.weebly.com/uploads/1/3/5/9/135958876/xuxobusaradek.pdfIn PDF document text
    • https://static.s123-cdn-static-d.com/uploads/4460045/normal_60aff3a2d7194.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4371261/normal_5ff80d55a6868.pdfIn PDF document text
    • https://fibumexil.weebly.com/uploads/1/3/1/0/131070733/554ae30d.pdfIn PDF document text
    • https://kowonuzadanovit.weebly.com/uploads/1/3/4/6/134686130/4315933.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4368246/normal_60bd2bfc4afd0.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4474169/normal_6040ac0339db7.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4393346/normal_5fd287c0677cc.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4416154/normal_5fc745995382d.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4458616/normal_5ff665a7dbc0b.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4495034/normal_60ba3dfed7796.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/1c79d806-f95e-4adb-bb7e-7a73e2c6aa71/rapidex_english_speaking_course_book_in_urdu_download.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/ed9146be-3b6e-4e77-9f8c-fb46482b6076/what_is_an_example_of_a_positive_attitude.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/2b771dbc-839f-491e-984b-19edd042fe6f/mental_status_exam_form.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/8cd8c3d7-d21e-465f-99ab-447cc6320d61/rutanan.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/f33676f0-2bc1-4a9e-860d-68eee6d067bb/which_phonological_processes_to_target_first.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/3efc4342-36b1-45f7-8946-f2ee42c2b98e/61759819094.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/057a5389-7a07-4d58-9fc7-f1df6655f286/bud_light_bud-e_fridge_for_sale.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_off000148ce.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x148CE 4940 bytes
SHA-256: e90539ee2be8e9b4549acee00108728b222c2b28acdec28bc3057ce7f15f3b19
font_01_sfnt_off0001598c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1598C 11888 bytes
SHA-256: b3fcc1ce6def82ec50d8970910c85afad63e52b584dd3dbfa65db373bdfd50d5