Malicious PDF — malware analysis report

Static analysis result for SHA-256 aac90b3d2a5f9589…

MALICIOUS

PDF

73.8 KB Created: 2021-05-25 11:52:12 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-23
MD5: 012531287866d8af008a1af88966a983 SHA-1: 9e464570f15a88a6e55d0ea587bfdebe053649cd SHA-256: aac90b3d2a5f9589414bb30d943da6c92cb0cc058ddd04fe038839b9b7c5cf24
126 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, suggesting a link farm or redirection scheme. The ML classifier strongly indicated maliciousness, and the presence of embedded URIs points towards an attempt to direct users to potentially harmful content. No scripts were extracted, but the overall structure and heuristic firings suggest a malicious document designed to lead users to external sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

Heuristics 5

  • 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://ponafet.ru/strik?utm_term=what+is+the+minimum+sentence+for+gun+possession PDF link annotation
    • https://static.s123-cdn-static.com/uploads/4466662/normal_5ff903e4efb5d.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4448731/normal_6056edfe6479a.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4452217/normal_5fe56f6ecbffc.pdfIn PDF document text
    • https://suzefajadovu.weebly.com/uploads/1/3/4/5/134592553/1150338.pdfIn PDF document text
    • https://ziropiwos.weebly.com/uploads/1/3/4/3/134311351/4dbcd0dff8a0bef.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4486982/normal_604375550a7a9.pdfIn PDF document text
    • https://fuvutefimege.weebly.com/uploads/1/3/1/4/131453053/genukod.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4417995/normal_601491b9e7b3b.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4415327/normal_600bc527f4115.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4412905/normal_5fd90ebeee59f.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4378155/normal_602d0bcb4e2ce.pdfIn PDF document text
    • https://xalojuxovev.weebly.com/uploads/1/3/0/7/130774978/4126787.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4412895/normal_602804e7d66eb.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4369508/normal_602464bd75ce3.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/cc36f45d-08dd-4763-b7b5-d5fe1e4af4fa/63861997316.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/b495d27f-6f07-474c-87e0-0c266aa59498/lux_tx500e_thermostat_troubleshooting.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/8ac77d23-36f0-4adb-bee0-083b423c1ddc/90588511432.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/eba429cb-9050-407c-b7eb-c111e80e7b61/tensile_stress_science_definition.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/2acaff76-a32b-4741-b98e-307a9287e621/massey_ferguson_135_diesel_tractor_parts.pdfIn PDF document text
    • https://s3.amazonaws.com/gelawiweza/gatilejonuxudasukivev.pdfIn PDF document text
    • https://s3.amazonaws.com/napisakaluja/nefiduwuvilib.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_off0000e23e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE23E 5408 bytes
SHA-256: 4236be94cfb1c403da9b8f7474c6a1b02ffa06accdcc492c16f091e9c769b0dc
font_01_sfnt_off0000f48e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF48E 10840 bytes
SHA-256: 6a2e2fc9b71c9ebdb793772068619b46bc6a188e6560c83bf235820ba8727c60