Malicious PDF — malware analysis report

Static analysis result for SHA-256 57dbe8a6127ab178…

MALICIOUS

PDF

71.6 KB Created: 2021-05-21 19:08:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-16
MD5: dcb0b4da2049b2dec0fcd1482aefe02f SHA-1: 2b721955c51780365fb9945fdcf426a2369c92e0 SHA-256: 57dbe8a6127ab178f4b1d57ca001bffc486b500c7be8d46a13191543e5f4d296
186 Risk Score

Malware Insights

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

The PDF contains numerous external links, many hosted on disposable domains, indicating a link farm or redirection scheme. The ClamAV detection and ML classifier strongly suggest malicious intent, likely related to phishing or malware distribution. While no scripts were explicitly extracted, the PDF structure and heuristic firings point towards the use of embedded JavaScript for malicious redirection.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

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://baarspo.ru/strik?utm_term=corex+process+of+iron+making+pdf PDF link annotation
    • https://didunebufanef.weebly.com/uploads/1/3/4/6/134680758/mujikosineduxane.pdfIn PDF document text
    • https://damelexivukek.weebly.com/uploads/1/3/4/7/134771288/6e441faf.pdfIn PDF document text
    • https://tajuweselu.weebly.com/uploads/1/3/4/3/134362517/tuzesizupiseger-supuzuwej-fugediri-febelelaxup.pdfIn PDF document text
    • https://burerekubexu.weebly.com/uploads/1/3/1/3/131381452/3104673.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4377909/normal_5fed1fede403c.pdfIn PDF document text
    • https://gufogejerujog.weebly.com/uploads/1/3/1/4/131406717/bevorakeb_wikikod.pdfIn PDF document text
    • https://xadifopelizil.weebly.com/uploads/1/3/4/7/134771643/3643424.pdfIn PDF document text
    • https://bumobuzeki.weebly.com/uploads/1/3/4/4/134477779/pejinemixu-lopavirebaf-kutikobudax.pdfIn PDF document text
    • https://dewotime.weebly.com/uploads/1/3/1/6/131606762/406a06087901e11.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4501027/normal_603c45e9a7791.pdfIn PDF document text
    • https://kepiloxuxamife.weebly.com/uploads/1/3/0/7/130740378/najed.pdfIn PDF document text
    • https://folejate.weebly.com/uploads/1/3/4/9/134902611/munozawawexud.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4377679/normal_6016c3a216889.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4393029/normal_605991557f1c6.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4371509/normal_6037172edb002.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4411500/normal_5fe86b00e4e4c.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4476924/normal_601bcf44e3641.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4412894/normal_60489f00db050.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://s3.amazonaws.com/najubu/kogula.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/a872e083-71e6-4683-ac14-1f7150808666/how_to_use_bragg_apple_cider_vinegar_for_face_in_tamil.pdfIn PDF document text
    • https://s3.amazonaws.com/muvarelo/how_to_use_a_quote_for_a_topic_sentence_dbq.pdfIn PDF document text
    • https://s3.amazonaws.com/kakekojezutok/school_days_apk_mod_net.pdfIn PDF document text
    • https://s3.amazonaws.com/xipavir/12246706495.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/3f00a47b-d2b0-4737-a97e-4b82e54f85fd/charcoal_grilled_bbq_ribs_recipe.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_off0000da4a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDA4A 5480 bytes
SHA-256: cd97a323470396b0e19deda9422dad2abf04ae6ab26b1b453d8154a381d8b047
font_01_sfnt_off0000ecde.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xECDE 10492 bytes
SHA-256: 1523a3542f75f24b954374b3880b3b6e47188ba5d2458040c6b75bae2877e753