Malicious PDF — malware analysis report

Static analysis result for SHA-256 b71c2264d9e9d330…

MALICIOUS

PDF

81.4 KB Created: 2021-05-29 07:54:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-24
MD5: 259a57a352d700b5e27046d689361442 SHA-1: 0447b20332d502130f274be12a55bd27141819be SHA-256: b71c2264d9e9d330d7f9319da2a010d071888a3579278f45ed7ba40fe8176a03
156 Risk Score

Malware Insights

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

The PDF file contains numerous external links, with a primary focus on directing users to 'soxebez.ru'. The heuristic 'PDF_SEO_LINK_FARM' indicates a large number of external links, suggesting an attempt to create a link farm or distribute malicious content. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or a scam, by leveraging a lure related to a 'Backlog certificate format'. No scripts were extracted, but the embedded URLs are the primary indicators of compromise.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 5

  • 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.
  • 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://soxebez.ru/strik?utm_term=backlog+certificate+format PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4489041/normal_606774284ebfb.pdfIn PDF document text
    • https://static.s123-cdn-static-d.com/uploads/4366035/normal_60b18ead5d0ea.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4452839/normal_6024abc91d58c.pdfIn PDF document text
    • https://xegavepixax.weebly.com/uploads/1/3/1/4/131452872/6015144.pdfIn PDF document text
    • https://wegoboxup.weebly.com/uploads/1/3/4/7/134772399/pupifazogike_warekolusenaxa_mirunexiwi.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4479235/normal_6011ef84e539a.pdfIn PDF document text
    • https://fupefomaxoxaje.weebly.com/uploads/1/3/4/8/134897629/822134.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/58b481b3-bcce-4455-bd50-ded64edeb731/how_to_reply_boss_email_sample.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/ec5817ea-98f0-4499-9401-81601a2b9b37/pirates_of_caribbean_1_full_movie_in_tamil_download.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/3a98c490-499d-4b78-8d47-22a87232c215/xekegojamatajemexe.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/43824cc5-0b46-4d3e-ace1-521c404b4984/puxuligujakomanuna.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/965df92e-4481-4eb9-b435-072f1bb08b7c/sukesufujazimexodobov.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/ee49e1cd-2a5c-498e-bbbd-389abd3efb64/watch_a_river_runs_thru_it.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/66bfab0b-c0ee-4091-853b-80a12b1dadef/zubupetidud.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/edb4a796-d506-47ae-a28a-b4c3722ee1b9/polaroid_sx_70_flash.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/9b60e982-cde7-4237-845a-398f2078a727/standard_deviation_ppt_tes.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/c6f6300a-0c73-4114-b8ea-74cdf7752146/how_do_i_say_the_apostles_creed.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/5c682871-c9dd-482e-b913-0c86385f60a2/nabevizurogusudurawum.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/6c5f9b8c-eb77-4a96-b041-f47dc5acd83b/geometry_common_core_pearson_online_textbook.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/72bea1ec-2bac-41f9-a6f3-791a395a882b/3_beeps_eject_ps4.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_off0000ffbd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFFBD 5136 bytes
SHA-256: 17a73f87084c9a9489e70cdf0f67ed99f873045850cc5de2e6ae7db358243bb7
font_01_sfnt_off0001112a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1112A 11028 bytes
SHA-256: 790299d19ec82272d8b4984c796ec240fccd51e13acae2219e9e71b4c3bb0d49