Malicious PDF — malware analysis report

Static analysis result for SHA-256 be66fd24b86c5315…

MALICIOUS

PDF

76.3 KB Created: 2021-06-03 19:33:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-23
MD5: a6151fb1d88bb99437c7afea1719ea21 SHA-1: a3974af7f7b8cfe90186f0a6b126edde76c6c3ac SHA-256: be66fd24b86c5315c22bfa9118a43a963ad278edafb8b22d72f8197b44f48751
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 0.9990

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://dafemum.ru/123?utm_term=freddie+mac+relief+refinance+underwriting+guidelines PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4469824/normal_60498ee5e6b64.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4450350/normal_602aa9e5c3461.pdfIn PDF document text
    • https://nelibijejukeli.weebly.com/uploads/1/3/1/4/131437261/vewifum.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4488332/normal_5ff58ab254801.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4485568/normal_605cedd6dfab4.pdfIn PDF document text
    • https://mikujisevoj.weebly.com/uploads/1/3/7/5/137511904/taxibolimatos.pdfIn PDF document text
    • https://tusutaxuwipafu.weebly.com/uploads/1/3/4/4/134403355/1028857.pdfIn PDF document text
    • https://vituxusupodewe.weebly.com/uploads/1/3/1/3/131379836/metebu-mofoluka-mikife-nizodo.pdfIn PDF document text
    • https://vesogotupu.weebly.com/uploads/1/3/4/7/134702950/4326c2095dabb8.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4387056/normal_5fdc655a1d69c.pdfIn PDF document text
    • https://nuzunuge.weebly.com/uploads/1/3/5/3/135399682/703f5.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4486521/normal_6014d05bac82d.pdfIn PDF document text
    • https://semitedajun.weebly.com/uploads/1/3/1/6/131636975/5344201.pdfIn PDF document text
    • https://josojizaxa.weebly.com/uploads/1/3/5/9/135966587/e69fc7e6d9.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4425483/normal_603aa21401771.pdfIn PDF document text
    • https://bevozuvegala.weebly.com/uploads/1/3/3/9/133999301/1176094.pdfIn PDF document text
    • https://fasexonepagi.weebly.com/uploads/1/3/0/9/130969542/4184439.pdfIn PDF document text
    • https://disepijov.weebly.com/uploads/1/3/1/4/131438002/fisedabukoj_fajaxuxibi_nurav_saliwozananu.pdfIn PDF document text
    • https://silepokow.weebly.com/uploads/1/3/4/3/134366863/wovinejo.pdfIn PDF document text
    • https://nipibodofabujid.weebly.com/uploads/1/3/4/2/134265940/5797649.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/3dd76c50-c559-49f8-957d-bbb4a4f65828/active_and_passive_voice_exercises_for_ssc.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/369c46e5-1055-4b54-8e3f-d156dcd13896/which_is_the_best_hidden_camera_detector_app.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/b2ddcd06-e454-43c9-aeff-07f3ee5350ad/2379327165.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/b4faa547-6f14-4506-998d-7b102d986337/93689277270.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_off0000eafc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEAFC 5388 bytes
SHA-256: 3d28fd9b14facfa5061d066eb4ad9c8f228a0412483fadd31290d67bccaaf03d
font_01_sfnt_off0000fd4e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD4E 10776 bytes
SHA-256: fb99e2693bd367de8853e65f521e4a3987891f73dcfb59a696f66a617646d70f