Malicious PDF — malware analysis report

Static analysis result for SHA-256 7c7acfde3607a335…

MALICIOUS

PDF

77.9 KB Created: 2021-04-01 08:46:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-07-13
MD5: 2ecd80a09e9248b7415f6dabc3c911b7 SHA-1: fa36819e7d69f38d40fdd6287c7708ba41b36c6c SHA-256: 7c7acfde3607a33540cb31f4d6fd80690d7443e80c1b0e56dff9c6aecfe5cd33
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, suggesting a link farm designed to redirect users to malicious sites. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution. The embedded URLs and the PDF's structure point towards a tactic of using search engine optimization (SEO) lures to attract victims.

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://midufefew.ru/award?keyword=maya+animation+books+pdf PDF link annotation
    • https://gavuwili.weebly.com/uploads/1/3/1/0/131070236/0ee55fdfef528e.pdfIn PDF document text
    • https://jizanisa.weebly.com/uploads/1/3/5/3/135386656/caff88e2749.pdfIn PDF document text
    • https://gaxifuxizuru.weebly.com/uploads/1/3/0/7/130739475/rakaxivutodapur-tomedezor.pdfIn PDF document text
    • https://dexetejitifite.weebly.com/uploads/1/3/4/5/134576896/lisalewuwo.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4392651/normal_603e4e2552a7b.pdfIn PDF document text
    • https://gagakulusete.weebly.com/uploads/1/3/5/3/135326625/96a36d7d209c.pdfIn PDF document text
    • https://gevexivojuler.weebly.com/uploads/1/3/4/4/134444242/rusiseniduloden.pdfIn PDF document text
    • https://sinegaxoxu.weebly.com/uploads/1/3/4/4/134462527/kajobovun-jovuniluta.pdfIn PDF document text
    • https://fosobezi.weebly.com/uploads/1/3/4/8/134898374/1e077.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/4963d39e-ea75-4f45-84c2-6593e7e95ece/security_analysis_benjamin_graham_sixth_edition.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/1c6731f6-353d-4233-b5c6-b20742a882db/rapat.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/d7f1b697-9e92-4c7b-9cf4-56d3bcf2b2d9/vocabulary_builder_app_ios.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/44313db6-c3dd-4941-905a-38253468fd9c/movejilove.pdfIn PDF document text
    • https://e082b6be-64c0-45f6-a8ff-82b9c6f476f0.filesusr.com/ugd/1479de_cf63d5ec7b1f4554974396b4dc040a0b.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/95b90cf2-fe8e-46c7-9fc4-f3329914b8f0/britax_frontier_clicktight_installation.pdfIn PDF document text
    • https://52a1af19-6946-4c37-aba6-ab00a30e4874.filesusr.com/ugd/5dc3ca_10daa0f6c47f4260960431eef4f6de07.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/5f9e92ea-6451-4783-9947-59039e719dfb/what_is_descriptive_quantitative_research_design.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/1912a5b9-74b9-4a90-9573-1a2b4562f588/78582357871.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/a1832b8b-e851-4ced-ab55-66091536cad8/senior_it_systems_engineer_job_description.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_off0000f373.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF373 5368 bytes
SHA-256: b36845262a5282c8b908762cdf4c4d31978bc9dfe3eb0d6ae55e81d33a345f3f
font_01_sfnt_off000105bc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x105BC 10664 bytes
SHA-256: 2d6f35584405b252023d5eba0395d9cbbff40bfb5236c4047ec8c9c761a17723