Malicious PDF — malware analysis report

Static analysis result for SHA-256 8072b57555c57ff8…

MALICIOUS

PDF

89.8 KB Created: 2021-05-03 14:42:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-02
MD5: 09fec0e93fa8e8958ce937857fa6c72a SHA-1: 24fc2e40d63ae2fabfff08880a806abbcfde21ec SHA-256: 8072b57555c57ff82b983fda1963f3bc5f88fc79047b6007b75a02f9099f83eb
186 Risk Score

Malware Insights

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

The PDF contains numerous external links, many pointing to disposable domains, suggesting a link farm or SEO poisoning tactic to distribute malware. The ML classifier and ClamAV detection strongly indicate malicious intent. While no scripts were directly extracted, the PDF structure and heuristic firings point towards a phishing or malware distribution scheme.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9993

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://maypoin.ru/strik?utm_term=nester%2527s+microbiology+a+human+perspective+9th+edition+pdf+free+download PDF link annotation
    • http://mavpa.fun/3960697822uycc6.pdfIn PDF document text
    • http://about-central.com/foxekeduraxkwajm.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4473656/normal_5fda2aebd3f70.pdfIn PDF document text
    • https://datotumegodipe.weebly.com/uploads/1/3/2/7/132740351/09a9ba7854.pdfIn PDF document text
    • http://arthromedro.xyz/attack_on_titan_game_pc_controlsgju5h.pdfIn PDF document text
    • http://magic-spring.com/15952638083ci25x.pdfIn PDF document text
    • https://bejeselujolir.weebly.com/uploads/1/3/1/3/131379719/wejese_korajeferawud.pdfIn PDF document text
    • https://sopidafepu.weebly.com/uploads/1/3/4/7/134744384/xiwexin.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4412761/normal_600670db7fda7.pdfIn PDF document text
    • https://gupufema.weebly.com/uploads/1/3/4/4/134456882/1182681.pdfIn PDF document text
    • https://linugezi.weebly.com/uploads/1/3/4/2/134265501/8329199.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4460057/normal_603deb96ae872.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/e91cacf0-cde4-4be1-92ca-c1e7be596d83/formula_estructural_acido_clorhidrico.pdfIn PDF document text
    • https://s3.amazonaws.com/nolarifaforuxop/60232479127.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/fc59143d-cacb-43d4-b1eb-0ff2e3440e43/ti-30x_iis_convert_to_fraction.pdfIn PDF document text
    • https://s3.amazonaws.com/kavalukato/a_clash_of_kings_weebly.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/5c91a719-fb59-4c0e-a8b8-775604dd57b1/74672118666.pdfIn PDF document text
    • https://s3.amazonaws.com/gofilafixu/nunafavuduto.pdfIn PDF document text
    • https://s3.amazonaws.com/zesixefe/christmas_jazz_fake_book.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/9019fa9d-b6ef-4e65-9e51-9c4b23482cca/rekudapivatozofifokopomip.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/bcef085e-ca90-420d-afec-8be8bd4ba109/majestic_gas_fireplace_not_turning_on.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/b3d113ab-40c3-41c3-8f8a-f3ffdfe937bb/45082924250.pdfIn PDF document text
    • https://s3.amazonaws.com/vazisi/how_to_start_a_keto_meal_plan.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/34fb57ee-89bd-49aa-ae56-62174c4fe50e/how_to_light_a_coleman_heater.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_off00011d24.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11D24 6120 bytes
SHA-256: aea9526f75c7a3bda4a63bb3d7749c4c26cb1d4901cb423daafd1f14546beb2e
font_01_sfnt_off000131f2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x131F2 10904 bytes
SHA-256: faea77a90c952ab00207ef7c4a97def81a26bf8d428193042e05d78df68d493e