Malicious PDF — malware analysis report

Static analysis result for SHA-256 a613ba2ef59b9628…

MALICIOUS

PDF

77.6 KB Created: 2021-04-04 16:36:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-07-13
MD5: cbb2c768f9a09f60cb6405afbd3d7c13 SHA-1: d6b624e06487e9899e130953bf4e96dc659880ee SHA-256: a613ba2ef59b9628e0124bb72fe15fbf58f9d7cb5b056c67f1ed3f2be739ce8b
186 Risk Score

Malware Insights

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

The PDF file contains a large number of external links, many pointing to other PDF files, indicating a link farm or SEO manipulation tactic. The ClamAV detection and ML classifier strongly suggest malicious intent, likely related to phishing or distributing further malware. No scripts were extracted, but the structure and URL patterns are indicative of a malicious document designed to lure users to external resources.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://druttle.ru/wix?keyword=covalent+bonding+and+molecular+compounds+worksheet+answers PDF link annotation
    • https://cdn.sqhk.co/jirudumom/hcN3rsf/54775951576.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4389599/normal_605b02e677ae0.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4498404/normal_5fc9d9c93dab9.pdfIn PDF document text
    • https://cdn.sqhk.co/gaxokakijefe/c7njfhi/zotadidoremano.pdfIn PDF document text
    • https://zetodimamewiwek.weebly.com/uploads/1/3/2/3/132302859/2231ffe0b2f.pdfIn PDF document text
    • http://fowozomogijib.iblogger.org/how_many_calories_in_a_small_wendys_vanilla_frosty.pdfIn PDF document text
    • http://piroluzufu.iblogger.org/australia_student_visa_checklist.pdfIn PDF document text
    • https://ruwevuvav.weebly.com/uploads/1/3/5/3/135387918/a3185962abf.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/962a64af-bac5-49fe-a65a-58f181e2281e/zeguvutitudoruxovo.pdfIn PDF document text
    • http://fowewimoseno.epizy.com/91541880342.pdfIn PDF document text
    • http://kagokonutuvep.epizy.com/2418836777.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/a47a69ea-364a-4719-bcf2-b49fd4f95e49/78470055042.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/97747efa-eab2-4ab9-a591-1aa892ad38c4/jomiximinirodipog.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/d0f183e5-f82a-4adf-8dfc-2947d716c8bf/bubinawez.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/c2fd46a4-98f2-4bc8-bcea-34a0c5925940/2006_honda_odyssey_touring_for_sale.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/8ea58549-51f0-4c9e-b29c-b553fb511476/medobe.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/56cddd15-1d04-4491-845d-ba227b0a3b11/dovapin.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/6d02c742-3714-44f7-85c5-f997e6da1e09/what_is_social_justice_in_health_and_social_care.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/274166ab-1e7a-427b-8085-f5be4b779c72/states_of_matter_quiz_3rd_grade.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_off0000e12f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE12F 5748 bytes
SHA-256: d3e3515dff22deacd49ca577a14fdd3988fb2f80f8cebdcf4856479fc45a004d
font_01_sfnt_off0000f4a7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF4A7 11112 bytes
SHA-256: d1a3d25795b53657f879bf22da4377319ebe180b7e7f023a393d07a5ad3bc28e
font_02_sfnt_off00011aad.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11AAD 4324 bytes
SHA-256: ff5f0ef16caf3e97cd1984b3a03ea88e11eab8cf63d2ee006085a4b9995833f3