Malicious PDF — malware analysis report

Static analysis result for SHA-256 da9caac093296367…

MALICIOUS

PDF

91.6 KB Created: 2021-05-28 20:52:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: b7bfbe7d94dd79a535a28d3ff51c0c50 SHA-1: d21d44f6bca262338ef26397e603f1982f309e7c SHA-256: da9caac093296367ae326fd5fef821b688b5a63ff2a74dc2161f82ca8001ecdc
156 Risk Score

Malware Insights

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

This PDF file was flagged by multiple heuristics and ClamAV as malicious, specifically as a phishing trojan. It contains a large number of external links, many pointing to PDF files hosted on various platforms, suggesting a link farm or redirection mechanism. The embedded URL `https://dafemum.ru/strik?utm_term=medical+microbiology+mcqs+with+answers+pdf` indicates a lure to a specific search query, likely to disguise malicious intent. While no scripts were explicitly extracted, the PDF structure and link farm behavior are indicative of malicious intent to redirect users to potentially harmful sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9988

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.
  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://dafemum.ru/strik?utm_term=medical+microbiology+mcqs+with+answers+pdf
    • https://cdn-cms.f-static.net/uploads/4457590/normal_60383dd634903.pdf
    • https://gumabudisipinef.weebly.com/uploads/1/3/2/7/132712006/jofipepixitopuden.pdf
    • https://vetidemilutuzu.weebly.com/uploads/1/3/4/4/134492936/ed8a0e2fea86b4.pdf
    • https://cdn-cms.f-static.net/uploads/4408720/normal_60489f370d209.pdf
    • https://firajapototirop.weebly.com/uploads/1/3/1/4/131452771/8282870.pdf
    • https://static.s123-cdn-static.com/uploads/4470980/normal_5fee68862e2b9.pdf
    • https://pamibatofenowa.weebly.com/uploads/1/3/4/5/134525539/wijubipu.pdf
    • https://cdn-cms.f-static.net/uploads/4452161/normal_6032dee8bc3df.pdf
    • https://static.s123-cdn-static.com/uploads/4462046/normal_6005ef7c31787.pdf
    • https://fipuzogafugigen.weebly.com/uploads/1/3/4/1/134108551/8985382.pdf
    • https://cdn-cms.f-static.net/uploads/4373782/normal_6041b300632e6.pdf
    • https://cdn-cms.f-static.net/uploads/4387920/normal_6028227609fb0.pdf
    • https://cdn-cms.f-static.net/uploads/4409840/normal_6047e2990f789.pdf
    • https://static.s123-cdn-static.com/uploads/4369651/normal_5feb7680ce49c.pdf
    • https://cdn-cms.f-static.net/uploads/4464530/normal_60214939b1064.pdf
    • https://cdn-cms.f-static.net/uploads/4413120/normal_5fe9c6d71ebad.pdf
    • https://dalideno.weebly.com/uploads/1/3/5/3/135384103/movereja_kepezitivizela.pdf
    • https://mojipidu.weebly.com/uploads/1/3/4/3/134391160/47f59674d6.pdf
    • https://cdn-cms.f-static.net/uploads/4408186/normal_6063f82ff2a26.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • http://www.daltonmaag.com/
    • https://uploads.strikinglycdn.com/files/aca6c415-9310-47be-8134-d424c164adc9/glacier_bay_faucet_parts_diagram.pdf
    • https://uploads.strikinglycdn.com/files/ed51e3df-77e4-445d-8685-6a7ec2b19f65/89697123479.pdf
    • https://uploads.strikinglycdn.com/files/0e1a9606-8ea3-43b0-9eac-76c07efe03cd/business_math_15th_edition_online_book.pdf
    • https://uploads.strikinglycdn.com/files/bc94911f-b465-4614-a489-384d38f47abc/gemekoremesegesek.pdf
    • https://uploads.strikinglycdn.com/files/fe6a723b-6f41-4e0c-9a4f-1fb2bc74c018/turtle_beach_stealth_420x_plus_transmitter.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://scripts.sil.org/OFL

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00011935.bin
84e1fcf10f1e5f857600a423cc59bcee762ce1828631d2d1712c6b285d59f2bf
pdf-font-stream PDF embedded font (sfnt) at offset 0x11935 5820 bytes
font_01_sfnt_off00012cde.bin
e53ca7c42581ff7ded8d3f45c5bfa54ad02e2221cc21f499687722ccb819e55c
pdf-font-stream PDF embedded font (sfnt) at offset 0x12CDE 11076 bytes
font_02_sfnt_off000152a3.bin
4fcfa7c68d76e23b667942a3ac892d2d5d88346478daafc61479ad4df4af3dd3
pdf-font-stream PDF embedded font (sfnt) at offset 0x152A3 4324 bytes