Malicious PDF — malware analysis report

Static analysis result for SHA-256 646795945c88a926…

MALICIOUS

PDF

76.1 KB Created: 2021-05-07 09:14:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-08-20
MD5: 7529eb3031eb5416d2823911b3fe9ef1 SHA-1: b1b78611cc784e5d9964fc16f37c92a844438133 SHA-256: 646795945c88a9260dc89b8d0ea7ad73d6e9f143753b5c8916782717836dd4b9
186 Risk Score

Malware Insights

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

The PDF file contains a large number of external links, many hosted on disposable domains, suggesting a link farm or phishing operation. The primary URL, 'https://resalured.ru/strik?utm_term=azar+grammar+blue+book+pdf', is designed to mimic a search result, likely to trick users into clicking through to malicious content. The ML classifier and ClamAV detection strongly indicate malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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://resalured.ru/strik?utm_term=azar+grammar+blue+book+pdf PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4484834/normal_5fd1f3e2a2ef7.pdfIn PDF document text
    • https://cdn.sqhk.co/veletafi/gdVigQ1/uefa_champions_league_2020_winner_odds.pdfIn PDF document text
    • https://livuwijonirib.weebly.com/uploads/1/3/4/7/134732661/7478030.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4384026/normal_600180d59bd8a.pdfIn PDF document text
    • https://jutulomivepira.weebly.com/uploads/1/3/4/7/134775876/2861981.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4415061/normal_60446e3885b43.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4454172/normal_6021449699818.pdfIn PDF document text
    • https://sodefabufu.weebly.com/uploads/1/3/4/4/134473286/ranizexuj.pdfIn PDF document text
    • https://cdn.sqhk.co/gituridewo/XOihhbJ/age_of_z_origins_tower_defense_level_15.pdfIn PDF document text
    • https://cdn.sqhk.co/fojevimexu/Zigtdha/holiday_office_dress_up_ideas.pdfIn PDF document text
    • https://cdn.sqhk.co/gikunixa/i8AGgiB/dragon_battle_games_download.pdfIn PDF document text
    • https://bitigufej.weebly.com/uploads/1/3/5/3/135337089/94058abca24068.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4376869/normal_5fd8898b203f1.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://s3.amazonaws.com/niporofez/all_computer_course_full_form.pdfIn PDF document text
    • https://dd67658a-cc17-4e1c-bca5-42bf299a485b.filesusr.com/ugd/07a440_fddbce6ba35f494ba54457eefd7d3cce.pdf?index=trueIn PDF document text
    • https://61249681-e2d1-4375-841a-b3723294d79c.filesusr.com/ugd/3d514e_21f33b20b02a4322b78d4c1e97c58eb6.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/gebukil/why_is_my_hot_water_not_hot_anymore.pdfIn PDF document text
    • https://3176e400-c268-4dc0-8d69-08eae86937f8.filesusr.com/ugd/ea2f88_9cbaeda94c0944ddbf92e26c1a2993c7.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/susonanezaj/alesis_dm10_user_guide.pdfIn PDF document text
    • https://s3.amazonaws.com/tasufagijaremo/law_dictionary_india.pdfIn PDF document text
    • https://s3.amazonaws.com/levumoduf/motorcycle_in_gear_but_wont_move.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_off0000eb85.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEB85 5424 bytes
SHA-256: 2405ab46708c181d6ed9496f3e1f7eb855fa8c170b685eb80cae08764eaf8078
font_01_sfnt_off0000fdec.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFDEC 10952 bytes
SHA-256: 4f0c84ba2e83945ed5d1a23981d9baa54a5756e2e6c467b426bcd6a539607ba9