Malicious PDF — malware analysis report

Static analysis result for SHA-256 a2f5ce273ac7f1e8…

MALICIOUS

PDF

111.2 KB Created: 2021-06-08 00:30:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-24
MD5: 251699487e34eef5ba44976792f8c8c3 SHA-1: 47ebc780100016dadc775068799abdf3831c52ad SHA-256: a2f5ce273ac7f1e8ab3cd8d18c3e2c567e1d6923a1434359db853a38971a3d57
186 Risk Score

Malware Insights

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

The PDF was flagged by ClamAV as a phishing trojan and a machine learning model assigned a high probability of maliciousness. It contains a large number of external links, many pointing to disposable hosting, suggesting a link farm designed to distribute malicious content or phish users. The presence of embedded URLs and the PDF_SEO_LINK_FARM heuristic indicate the primary function is to redirect users to potentially harmful sites.

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://chcial.ru/pbw?utm_term=aeronautical+information+publication+%2528aip%2529+indonesia PDF link annotation
    • https://bubixumijek.weebly.com/uploads/1/3/5/3/135397401/jifetik_sewux.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4374954/normal_5fda1edf4d928.pdfIn PDF document text
    • https://rawuvuxa.weebly.com/uploads/1/3/4/0/134019107/c6cabc5c288074.pdfIn PDF document text
    • https://zajolapa.weebly.com/uploads/1/3/0/7/130776493/b13c3d04.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4420767/normal_605c28404e88d.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4382790/normal_6053af130772d.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4410418/normal_5ff964b3ef3e8.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4414360/normal_60b9d72e1a5ed.pdfIn PDF document text
    • https://ferakatetimof.weebly.com/uploads/1/3/4/4/134470639/powikufasuzazi.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • https://uploads.strikinglycdn.com/files/b8a3a8f4-2445-4929-8480-bc0454998de2/audio_technica_turntable_lp60x_review.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/0c071c88-9914-4063-af88-cbf80b147fda/7548885446.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/fd2a7a61-7978-4df3-b871-4e8631246ef4/78319508436.pdfIn PDF document text
    • http://tejudafo.pbworks.com/f/different_ways_to_name_a_plane_in_geometry.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/1bd17b95-9293-4383-8532-b1fbbb9ca18f/savaxezavajufoxenuzi.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/60df4dc9-4743-4af5-b44f-dc2d43d5e9b0/libro_para_colorear_netter.pdfIn PDF document text
    • http://zepadatoju.pbworks.com/f/is_tracfone_iphone_unlocked.pdfIn PDF document text
    • http://midevodimu.pbworks.com/w/file/fetch/144447909/sql_server_management_studio.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/90838b8b-add2-49b9-a38e-544b91fd98bf/jatewozejifagubupumigub.pdfIn PDF document text
    • http://kokoxudalux.pbworks.com/f/84722454012.pdfIn PDF document text
    • http://zilebunod.pbworks.com/w/file/fetch/144676362/halo_2_xbox_360_lt_3.0.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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000164d7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x164D7 5464 bytes
SHA-256: a61633aa5e34320c6ca7de47234bfac199ca6c202435aca4b2e62491c44b2591
font_01_sfnt_off0001774f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1774F 12284 bytes
SHA-256: e0676e13ae0cb65c4c2869f966f88f3f1fd49d82072345dbd6f2d90732b7fe20
font_02_sfnt_off0001a114.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1A114 4324 bytes
SHA-256: 9f355172d696dda274cac500966718f112ce76951f19577ac4888987ea6471b2