Malicious PDF — malware analysis report

Static analysis result for SHA-256 e31366229b1ff928…

MALICIOUS

PDF

82.7 KB Created: 2021-04-25 15:11:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-20
MD5: d9af08d129780476c42f6d706d55872e SHA-1: 7eda3c5e601260c3b5dd83c57e0963aed262f330 SHA-256: e31366229b1ff9282edcc976e69ce299bab487ddfff68212b485db47e1673565
186 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

This PDF file was identified as malicious by ML classifiers and ClamAV, indicating a phishing or trojan threat. It contains a large number of external links, suggesting it functions as a link farm. The primary malicious activity appears to be directing users to potentially harmful content hosted on external domains, as evidenced by the PDF_SEO_LINK_FARM heuristic.

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://jacksth.ru/strik?utm_term=star+chart+poster+custom PDF link annotation
    • https://static.s123-cdn-static.com/uploads/4366407/normal_60060aaa3a802.pdfIn PDF document text
    • https://cdn.sqhk.co/feketukadoz/gfRIhih/advance_auto_parts_jobs_warehouse.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4410448/normal_5fd18767ac631.pdfIn PDF document text
    • https://cdn.sqhk.co/mudemodox/jXvcmMR/9590908435.pdfIn PDF document text
    • http://form-copyrightservices.com/determine_the_machines_second-yearh6jr6.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4383917/normal_603ad0700bf75.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4449615/normal_5feb894e0c1ef.pdfIn PDF document text
    • https://cdn.sqhk.co/genamudazunu/k1gdjjg/60654720344.pdfIn PDF document text
    • https://cdn.sqhk.co/xakelafu/0TW0vBK/49237975798.pdfIn PDF document text
    • http://terem.space/37979490551pb5my.pdfIn PDF document text
    • http://trastenmyqort.online/introduction_to_christian_ethics_lovinaad3g.pdfIn PDF document text
    • https://cdn.sqhk.co/dazulegug/aifiac0/fps_strike_3d_free_online_shooting_games_unblocked.pdfIn PDF document text
    • http://ighelperscenter.com/learn_how_to_play_the_alto_saxophonez445g.pdfIn PDF document text
    • http://jutovutivori.22web.org/36307059604.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://bf23b77b-49a9-4bef-a898-a03cfb94aefa.filesusr.com/ugd/134172_06bb989ad54040cc91fef72e8ca22ba2.pdf?index=trueIn PDF document text
    • https://299bc67c-4c9a-44ea-852c-18f2d39dca40.filesusr.com/ugd/954c8b_4978604bffa542199ad6bbac8f535833.pdf?index=trueIn PDF document text
    • https://43cb2d18-1589-43a7-b1c5-fe1278e1c76d.filesusr.com/ugd/370b54_1814cdafaf7f41d5809b176495e1b414.pdf?index=trueIn PDF document text
    • https://2c9641c8-5874-4869-9b94-f1378e60aa6b.filesusr.com/ugd/efc1f6_df29593cf9de4f58ad0303ee2435164e.pdf?index=trueIn PDF document text
    • https://a72a44ae-2aae-4d6a-a6c4-235301d0a62e.filesusr.com/ugd/57436b_b5b95ca7923c47cab569094e056cc8da.pdf?index=trueIn PDF document text
    • http://ziwitiko.epizy.com/luxalutiguwarunibewedeku.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
    • https://savannah.gnu.org/projects/freefont/In PDF document text
    • http://www.gnu.org/licenses/In PDF document text
    • http://www.gnu.org/copyleft/gpl.htmlIn 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_off0000ed65.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED65 6676 bytes
SHA-256: eb818d908f85100d3a99250672f03864bcbe34b2514f2b59354f321a79477503
font_01_sfnt_off0000fe38.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFE38 5244 bytes
SHA-256: 0eb77a0b0847d83925d9c3c0b6a81ab1a8280be28f421be45ebae1b3f17df4a0
font_02_sfnt_off00010fe0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10FE0 12788 bytes
SHA-256: 5de444560d3f0071abc4f54cf062b64673e0e35a3249f2c8bf19e6c9360759b9