Malicious PDF — malware analysis report

Static analysis result for SHA-256 5076bde4a593f0f3…

MALICIOUS

PDF

85.4 KB Created: 2021-06-09 19:30:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-24
MD5: 8d08ac48779c8045a546b12f10db1388 SHA-1: cc114b78f9b24479c4143164a5cd66a591378079 SHA-256: 5076bde4a593f0f37cb08b212dd8f3da59705aef304bbd61e3aeee3f93f84fae
186 Risk Score

Malware Insights

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

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9995

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://synerhu.ru/pbw?utm_term=tricky+java+programming+questions PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4474191/normal_60642256b7d80.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4379030/normal_5fc9938d2aa1d.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4370055/normal_5fee353d7cd50.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4413977/normal_6056f4cfb90df.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4473926/normal_5fc8a256a64b3.pdfIn PDF document text
    • https://linowatudevenur.weebly.com/uploads/1/3/4/5/134599813/9a7aea882bd8.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4450638/normal_5fff4e2ed4a05.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4403823/normal_603487775b526.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4422631/normal_601d55c9693a6.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4369626/normal_603fe90f85a50.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4376358/normal_603289a2a24f7.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4423195/normal_60061559742e4.pdfIn PDF document text
    • https://tegomufowake.weebly.com/uploads/1/3/5/9/135958876/9402221.pdfIn PDF document text
    • https://femomupine.weebly.com/uploads/1/3/4/4/134458898/d7209e2a904c.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4426556/normal_6036dceb97b88.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4393641/normal_601ac627539a4.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://uploads.strikinglycdn.com/files/cd30c498-f26b-489c-87e4-03131f7aae5b/69227787791.pdfIn PDF document text
    • http://gitixofipoxu.pbworks.com/w/file/fetch/144601875/breckwell_pellet_stove_parts_p24.pdfIn PDF document text
    • http://bofamawetodo.pbworks.com/f/what_is_the_best_exercise_for_fat_burning.pdfIn PDF document text
    • http://vafobotigef.pbworks.com/w/file/fetch/144498807/what_is_the_principle_of_operation_of_a_hydraulic_brake_system.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/da263300-227a-4afd-bfac-d9f277b10d53/pogrom_oxford_english_dictionary.pdfIn PDF document text
    • http://fomebin.pbworks.com/w/file/fetch/144878835/12th_chemistry_2nd_volume_book.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_off00010064.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10064 5480 bytes
SHA-256: f8a2448f6a7231d801f357b1bad4c7a978f7ebb0441e892e9434b1cf678a0d74
font_01_sfnt_off00011302.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11302 11320 bytes
SHA-256: d16474fe7c86fac5405eec06b14c68a2575a0df1f4766ed2f3cdf18b3aaf7884
font_02_sfnt_off000139a5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x139A5 4324 bytes
SHA-256: ff5f0ef16caf3e97cd1984b3a03ea88e11eab8cf63d2ee006085a4b9995833f3