Malicious PDF — malware analysis report

Static analysis result for SHA-256 1f266144fb34069a…

MALICIOUS

PDF

78.5 KB Created: 2021-04-10 15:45:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-24
MD5: 5b8af36b35990038b60918354366ce34 SHA-1: 514a46fea5ea5fafca5b1c8cf12d19fe1fe476ec SHA-256: 1f266144fb34069a516c6173b20f3c2a6bdcce6096fd72efe437aa46f21ea3ad
186 Risk Score

Malware Insights

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

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

Heuristics 6

  • 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.
  • 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://nipisod.ru/strik?utm_term=2005+infiniti+g35+coupe+transmission+fluid+type PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4479923/normal_606dcee3b6c23.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4475720/normal_60624d6c0a9e5.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4375210/normal_5fe6917fde3ed.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4416810/normal_5ff069fb29151.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4389394/normal_6042d3696f8ff.pdfIn PDF document text
    • http://adv-workshop.site/51889966008t4anu.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4458827/normal_5fe2b5c4399f8.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4481059/normal_5fd90ffd31399.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4385417/normal_5ffa6d794b44e.pdfIn PDF document text
    • http://stav-games.ru/hp_laserjet_pro_400_m451dn_toner6503j.pdfIn PDF document text
    • http://clobuss.ru/150879131623361.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/fd5d2df0-6b5c-4a2e-8e89-c87bb6ae325c/poisson_process_example.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/049bc7ea-e90a-4616-883f-19d012a22acd/lekafop.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/91c19680-d758-463f-9a86-5eb7dfac32a9/53078260986.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/8cb1ecaf-59be-4e53-b36b-13ceed456759/varaso.pdfIn PDF document text
    • https://5a2ada08-5b6c-402a-b0df-3636415b461e.filesusr.com/ugd/434ae6_f618deefcdad42e8a0c81daba00d2fe0.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/f293cc05-6fe2-4b71-8dea-773d96e22fc3/nepaxe.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/6b234e23-9f42-4594-a896-bdea209197fc/pupatovawuxusop.pdfIn PDF document text
    • https://c751e6e8-0850-424d-b14e-d7ae46260796.filesusr.com/ugd/bc1028_f2a835c4e5324dd59bc1178b05bee11c.pdf?index=trueIn PDF document text
    • https://dacf5b84-f80e-4bd8-bb7f-22aad20a1cd8.filesusr.com/ugd/285be4_753f63c026ee40eca3504ec5369706e8.pdf?index=trueIn PDF document text
    • https://29159626-56e2-4eb2-a8c1-eb081f451e44.filesusr.com/ugd/a58502_3fa52f1d9b4c49168f0e632ab9d73d43.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/243cab41-d6ad-4d89-9155-46f7f12b3559/para_que_sirve_el_zinc_sulfate.pdfIn PDF document text
    • https://ce55c564-0e79-48ac-bd91-a034cff8554b.filesusr.com/ugd/bd1fc0_dc8afb59068d4598840060e78cde83e9.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_off0000f317.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF317 6044 bytes
SHA-256: 10b8a19e0070d84883416828d263044ae13c689ac189f9be1c17d098dc84f99f
font_01_sfnt_off0001079a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1079A 10636 bytes
SHA-256: 76c66949394e470e1e2ddb346cd5431027d6f8e35919f985effc2442cfbcdc69