Malicious PDF — malware analysis report

Static analysis result for SHA-256 a4bf3fb5871e226f…

MALICIOUS

PDF

77.6 KB Created: 2021-06-05 09:29:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-25
MD5: bcd2b9965cd7bca976bcda00c5689827 SHA-1: 9157ef369baa6038a234dac31ae5bc2a5f4f3316 SHA-256: a4bf3fb5871e226f2600492b7caff0d793021d70bf7ca9a47c0f808d07730024
186 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file contains a large number of external links, many pointing to disposable domains and hosted on services like Weebly and Strikingly. Heuristics indicate this is a link farm, likely for SEO manipulation or to distribute further malware. The ML classifier and ClamAV detection strongly suggest malicious intent, with the primary goal appearing to be directing users to potentially harmful external content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9995

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://laborke.ru/pbw?utm_term=dragonet+prophecy+graphic+novel+series PDF link annotation
    • https://gedikitol.weebly.com/uploads/1/3/4/9/134901051/5923740.pdfIn PDF document text
    • https://fukekagike.weebly.com/uploads/1/3/4/5/134587407/javinotivufemimexo.pdfIn PDF document text
    • https://wadidomewagu.weebly.com/uploads/1/3/2/6/132681938/9908814.pdfIn PDF document text
    • https://ragajepegoxi.weebly.com/uploads/1/3/1/3/131379061/8297293.pdfIn PDF document text
    • https://vejiledulibona.weebly.com/uploads/1/3/4/3/134318828/9091779.pdfIn PDF document text
    • https://sikapekit.weebly.com/uploads/1/3/5/3/135317012/6203538.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
    • http://pazimonofe.pbworks.com/f/christmas_coordinate_graphing_worksheets_free.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/95aac111-b6a9-4544-842a-79160fc415a4/91130256874.pdfIn PDF document text
    • http://sutodoromar.pbworks.com/w/file/fetch/144506232/java_1.7_64_bit_download.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/09040950-c5d4-464e-9208-abfadbd14419/xevokoburubufara.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/a45925df-48cd-42d9-8d38-472ad2524684/vovilimenerixe.pdfIn PDF document text
    • http://supatibu.pbworks.com/w/file/fetch/144654468/context_clues_3.7_worksheet_answer_key.pdfIn PDF document text
    • http://jolamibo.pbworks.com/w/file/fetch/144651597/noxofexanuzagezoxojaza.pdfIn PDF document text
    • http://taxexuwej.pbworks.com/w/file/fetch/144648942/10816895614.pdfIn PDF document text
    • http://kokoxudalux.pbworks.com/w/file/fetch/144421116/nemak.pdfIn PDF document text
    • http://nugewil.pbworks.com/f/rubovex.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/c57a16e7-fbc4-4615-bc37-c87be80fd218/how_was_the_us_governments_response_to_the_great_depression_different_after_franklin.pdfIn PDF document text
    • http://pulixojesu.pbworks.com/f/47331898137.pdfIn PDF document text
    • http://togiwuvoze.pbworks.com/w/file/fetch/144590514/nimusupunoxixox.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/d2810bf3-776d-4e42-a21e-48494eaf05a6/wd_live_hub_media_center_firmware.pdfIn PDF document text
    • http://zuvuzut.pbworks.com/w/file/fetch/144621225/artificial_selection_and_natural_selection_are_similar_in_what_way.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/5ef9c8f1-b7e5-45d2-b316-8ec2b2b00976/jekavaxopetonibuvu.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_off0000e0eb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE0EB 5144 bytes
SHA-256: 2d896c53ea8afb77cec27a6dff9048718670db68d02c619dfa36a7ee4c6124b2
font_01_sfnt_off0000f26c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF26C 11500 bytes
SHA-256: b5b7bb08188643331d34b1fd1b30489a2e65ca42ade9907f0abfaac441c84dbf
font_02_sfnt_off000118f7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x118F7 4324 bytes
SHA-256: 7f6049e5011acf0e8581793f2bc2bb947aac2929fdb77abc318b2a6155c1ef71