Malicious PDF — malware analysis report

Static analysis result for SHA-256 b9d87cef22e05b7e…

MALICIOUS

PDF

77.3 KB Created: 2021-05-22 11:43:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-25
MD5: 1e4d714952c303fb9d3d12c80d11d6c9 SHA-1: 42e2bff3a2525b1235ca9e59a31e2eac301a845a SHA-256: b9d87cef22e05b7e9184711d72307a8c571d33ad20655fa141db755370475282
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 file contains a large number of external links, many hosted on disposable domains, suggesting a link farm used for phishing or malware distribution. The embedded content, though heavily obfuscated, likely serves as a lure to these external resources.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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://leonvi.ru/strik?utm_term=python+programming+tutorial+pdf+tutorialspoint PDF link annotation
    • https://wefupavoxed.weebly.com/uploads/1/3/2/6/132682659/5058078.pdfIn PDF document text
    • https://liwitozawaben.weebly.com/uploads/1/3/4/0/134042828/nujibo.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4413983/normal_601e759955d54.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4404990/normal_5feb0b4761f5b.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4455196/normal_603095ec04417.pdfIn PDF document text
    • https://rulofobu.weebly.com/uploads/1/3/0/8/130814337/ragibod.pdfIn PDF document text
    • https://vojutodebol.weebly.com/uploads/1/3/4/0/134096580/3384901.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4385014/normal_605b3830b8e69.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4471710/normal_602bb3dd5a7b8.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4381098/normal_5fedcf4299347.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4493890/normal_5fdaf2cd8b0b6.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4474218/normal_606008705e430.pdfIn PDF document text
    • https://xexafuru.weebly.com/uploads/1/3/1/0/131070851/8309341.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/609d61f4-67b6-4609-9907-b64f0c10be90/43462901580.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/9ce89bae-eda7-43ba-bd7c-9908c5cb316c/97122118384.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/673c8bee-6d14-46ad-9295-e10dd437b4fa/halliday_resnick_walker_fundamentals_of_physics_8th_edition.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/93f2cf0d-d1d1-4c6d-9eed-0e9bf69c2f20/92711043547.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/30a61f50-29b0-4a85-93e3-af9fb4b1920b/what_are_the_readiness_skills.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/2520859c-0886-44de-96fa-841c0f3bbf42/xaxixemukawimefival.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/13466917-a9f8-4ccb-9b2c-9856c7cb6bf5/davuputom.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/8baf0986-ca79-490f-8ff5-4cdf7ca4c325/how_to_use_a_peacock_hand_warmer.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_off0000f048.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF048 5556 bytes
SHA-256: 321b0b246887204972e5a335ade2720ca5a11d7d005b5b2c1e9ac3b8a5fa9c03
font_01_sfnt_off00010311.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10311 10748 bytes
SHA-256: 0949d55cd3361d3779889a238c67f02b672233e833b6b3d17a5670abca43ba6b