Malicious PDF — malware analysis report

Static analysis result for SHA-256 caa085f9308f55f5…

MALICIOUS

PDF

82.5 KB Created: 2021-05-30 13:55:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-27
MD5: 1a32ae52793d1d7681ae6209b6def520 SHA-1: 4bcecb5e190a7bd70d2e9d09e0c4f2e555d3aea7 SHA-256: caa085f9308f55f5b63d1c426a25c8eaef2b4a8ff3b569ee8a9435c9f4714e4c
186 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many hosted on disposable domains, indicating a link farm or phishing operation. The ML classifier and ClamAV detection strongly suggest malicious intent. While no scripts were explicitly extracted, the PDF structure and embedded URLs point towards a malicious document designed to redirect users to potentially harmful sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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://dafemum.ru/strik?utm_term=ense%25C3%25B1anzas+para+ni%25C3%25B1os+cristianos+escuela+dominical PDF link annotation
    • https://zexiditituluw.weebly.com/uploads/1/3/4/7/134734655/niliwikijes.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4416806/normal_60259192867c5.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4414678/normal_6028989f5b54a.pdfIn PDF document text
    • https://zixavuxo.weebly.com/uploads/1/3/1/3/131398386/6787376.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4389387/normal_5fd9f2cfaf11f.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4478383/normal_60311d619a361.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4422906/normal_5fef4271d22c9.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4465255/normal_600d730716228.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4485163/normal_60659640ae7f5.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4405430/normal_601881d40c4b0.pdfIn PDF document text
    • https://femomupine.weebly.com/uploads/1/3/4/4/134458898/5963108c0.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4425759/normal_60387894c2d2e.pdfIn PDF document text
    • https://jewefero.weebly.com/uploads/1/3/1/3/131383264/napere_xejosokurinokel_bogipugabox.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4485930/normal_5ff0ec5778e83.pdfIn PDF document text
    • https://kowonuzadanovit.weebly.com/uploads/1/3/4/6/134686130/3143cae5d.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4421048/normal_603163a062385.pdfIn PDF document text
    • https://derunemutojo.weebly.com/uploads/1/3/7/5/137517297/5168919.pdfIn PDF document text
    • https://fajorisovobune.weebly.com/uploads/1/3/4/7/134752278/2453135.pdfIn PDF document text
    • https://ludubilataso.weebly.com/uploads/1/3/4/7/134719947/penidivanazuzojut.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/c483496b-4502-4583-b2f5-ac5ed8765968/why_is_my_evaporative_cooler_not_cooling.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/29cba49b-479f-4002-a153-5da211be1bef/56575696927.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/a967eca8-c6da-4e16-b05a-c87735508268/latest_diana_gabaldon_book.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_off000101e8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x101E8 5440 bytes
SHA-256: 18444e3229b0d6f86de7dc8b6b8dd2d7b6490914beb4d9f0fbdeac2c77a8463b
font_01_sfnt_off00011412.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11412 11644 bytes
SHA-256: 7848c3794faf00b9b41853ec71db0a16b2789224d0ce9c74553ac065c68c309c