Malicious PDF — malware analysis report

Static analysis result for SHA-256 19ee19645196d7d1…

MALICIOUS

PDF

87.7 KB Created: 2021-05-08 21:36:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-25
MD5: 42b676f177fc657142009dc414045748 SHA-1: 25bbb83c58a1500def18ffc8987b35c1dbed9729 SHA-256: 19ee19645196d7d1b6b660f520aa3e5952e20f8cfef11a476e27ae21ba4c2b53
186 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The heuristics reveal it functions as a link farm, directing users to numerous external URLs, including one on `midufefew.ru`. The document body, though heavily obfuscated, contains metadata suggesting it was generated by `wkhtmltopdf`, a tool often used to create SEO-optimized content or phishing lures. The presence of embedded URLs and the link farm behavior strongly suggest this document is designed to redirect users to potentially harmful sites, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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/strik?utm_term=what+is+administration+by+different+scholars PDF link annotation
    • https://cdn.sqhk.co/tijinujul/aji4gco/at_t_thanks_app_commercial_actor.pdfIn PDF document text
    • https://fenutirixe.weebly.com/uploads/1/3/4/6/134640366/bozedazazawid.pdfIn PDF document text
    • https://zitakusosexozi.weebly.com/uploads/1/3/4/5/134595565/pezabupaduvorevezado.pdfIn PDF document text
    • https://kapisodakogu.weebly.com/uploads/1/3/4/6/134697397/refefalalerejunukol.pdfIn PDF document text
    • https://cdn.sqhk.co/kolokejo/ZZFPFaw/3359886498.pdfIn PDF document text
    • https://tajafakedebufu.weebly.com/uploads/1/3/1/4/131438499/1849124.pdfIn PDF document text
    • https://nawawedivoxoni.weebly.com/uploads/1/3/4/7/134719505/7a1491710393e2e.pdfIn PDF document text
    • https://janolonixo.weebly.com/uploads/1/3/3/9/133987325/vamelozij.pdfIn PDF document text
    • https://woniwisupu.weebly.com/uploads/1/3/4/2/134266019/a53a9fd.pdfIn PDF document text
    • https://cdn.sqhk.co/gabixeme/jdhdvgf/kirajojirelifuva.pdfIn PDF document text
    • https://cdn.sqhk.co/rujiwujik/l4gh6ta/88590645340.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://b8f7bc2e-5f90-466c-a76c-b8215bfdb3ae.filesusr.com/ugd/9717d9_d95572c38edf43b4a5aca6c67dc5b80f.pdf?index=trueIn PDF document text
    • https://734e8db3-b9db-457c-abaa-08c06218e7ae.filesusr.com/ugd/f6bb82_d4f7c9f0d7484613b1262b0e4bd406de.pdf?index=trueIn PDF document text
    • https://8f6f9f04-f977-4239-955d-f6aecf2dd879.filesusr.com/ugd/81cd61_2c8ae9d5840d43ac95dfc5d7f9598dfe.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/7b6245ec-40be-44f5-b5ad-0cdeee9ff653/72072392316.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/c4f3f363-8802-4a66-a7a4-4864d0b39a12/2004_dodge_ram_1500_doors_for_sale.pdfIn PDF document text
    • https://bb491b24-4c81-4ccc-8daa-bf1baeb171c2.filesusr.com/ugd/93c935_2da89b8315fa44c2a3156ced61cf25b8.pdf?index=trueIn PDF document text
    • https://18aefb47-0221-41c7-ace0-4f78eb33e730.filesusr.com/ugd/bca722_3b82a500a72d4b6f8564d7df6ed5730a.pdf?index=trueIn 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_off0001169a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1169A 5516 bytes
SHA-256: f4d4af08f232f629eb3f19bc18069018ac9bfde6934d9ff144ef961b3c6e2cf7
font_01_sfnt_off00012943.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12943 12444 bytes
SHA-256: 52cbed2e33213093c2c7de05d306da4ef33320c6ce271ed30486a958cc216083