Malicious PDF — malware analysis report

Static analysis result for SHA-256 34186785fa3c9b75…

MALICIOUS

PDF

79.5 KB Created: 2021-03-08 10:56:56 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-18
MD5: aac63c944341d5fb36d619aa4c249cd2 SHA-1: bce7a41ccc898134dbf1d734bc5238ec9adbee9d SHA-256: 34186785fa3c9b7533b0e15bb5678e264a7911c543fb860d7c11a2ccc4ff397d
206 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many hosted on disposable domains, suggesting a link farm or SEO manipulation tactic. The ML classifier and ClamAV detection strongly indicate maliciousness. The embedded URLs and the heuristic 'PDF_SEO_LINK_FARM' point towards a campaign designed to drive traffic to various sites, potentially for advertising revenue or further malicious redirection.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 7

  • 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.
  • Callback phishing phone lure medium SE_CALLBACK_LURE
    Document asks the user to call a phone number in billing, refund, subscription, fraud, or security context — consistent with callback phishing or tech-support scam patterns. Suppressed for legitimate-issuer (IRS/gov/official-form) documents that carry no urgency or charge/dispute escalation.
  • 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://gimoguvi.ru/strik?utm_term=how+many+volts+is+a+riding+lawn+mower+battery PDF link annotation
    • https://nizawubanivud.weebly.com/uploads/1/3/4/5/134529200/wakema_bizomu.pdfIn PDF document text
    • https://junurewumopu.weebly.com/uploads/1/3/2/7/132740614/gewatawiboxefobido.pdfIn PDF document text
    • https://tugesarafexo.weebly.com/uploads/1/3/5/3/135319839/8dac8b647b63d16.pdfIn PDF document text
    • https://tizemafuniture.weebly.com/uploads/1/3/4/6/134636649/5583609.pdfIn PDF document text
    • http://kunabote.22web.org/calligraphy_letters_for_beginners_worksheets.pdfIn PDF document text
    • https://falatunasozenu.weebly.com/uploads/1/3/4/7/134762474/zofigu.pdfIn PDF document text
    • https://tagakokiginozol.weebly.com/uploads/1/3/0/7/130775172/muxix_tipab_kosoduf.pdfIn PDF document text
    • https://tijoramamuguko.weebly.com/uploads/1/3/5/3/135390581/53aea940c8f6.pdfIn PDF document text
    • https://nexajatolotol.weebly.com/uploads/1/3/4/3/134308242/vafetobup.pdfIn PDF document text
    • https://fekazivijiwawad.weebly.com/uploads/1/3/4/6/134687088/9556115.pdfIn PDF document text
    • https://dapunilak.weebly.com/uploads/1/3/4/5/134506399/5539773.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://e691ad07-92dc-45fa-af10-8929b4045ede.filesusr.com/ugd/87b9a8_04c698afcfec4dc3a921c5f8d5520e21.pdf?index=trueIn PDF document text
    • https://8316a071-1c81-4729-bbc9-bb84f51c1359.filesusr.com/ugd/b2ba6b_ccd49fa89dc04bc59ea46dc3418e25e7.pdf?index=trueIn PDF document text
    • http://xofiketur.rf.gd/independent_clause_worksheets_7th_grade.pdfIn PDF document text
    • https://d451e762-8e00-4155-9971-9512d28d2528.filesusr.com/ugd/b52961_92577ed10fa949caab7d89f7ca3f63ff.pdf?index=trueIn PDF document text
    • https://5e024257-ca51-40df-b6b5-a3104c7b7124.filesusr.com/ugd/97368a_ff0c449af3f245189cfd8a25554d6271.pdf?index=trueIn PDF document text
    • https://f59c0a4d-c104-43ac-8966-a5978cdf1b8c.filesusr.com/ugd/0c1ebd_9380372f88a847ddaad9909b577f7ad3.pdf?index=trueIn PDF document text
    • https://5a4e7950-e122-4b3c-9cf7-894e7f5b1216.filesusr.com/ugd/76aeb6_a9918c05587643fa9aa3b3c732f66683.pdf?index=trueIn PDF document text
    • https://67d298e0-85f4-4ad4-bf36-e1ac857e42fc.filesusr.com/ugd/b6bf5b_5648eef10496422e878c0a5ba65335bb.pdf?index=trueIn 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_off0000f87c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF87C 5500 bytes
SHA-256: 83a5a464c6cc4f0b2f2eb88d755d9ecdbaa3097e6082eb0744bae83c65b85fa1
font_01_sfnt_off00010b30.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10B30 10784 bytes
SHA-256: 047e686fdc256b8cc2e8a299b7a322d3a2c9f3ded2a4849c215dcb1f1ef8d6f9