Malicious PDF — malware analysis report

Static analysis result for SHA-256 fc0f197359b6d76f…

MALICIOUS

PDF

78.5 KB Created: 2021-03-20 00:44:42 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-27
MD5: 97e5bf270f2492ad1971a1f1fb662611 SHA-1: 61d1a3ec8ec4c881efefd434dc0d6aa91b057357 SHA-256: fc0f197359b6d76f010cf63779b70c2473f9e21b85105a1a9ad735df21cc02a8
186 Risk Score

Malware Insights

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

This PDF file was flagged by multiple heuristics and an ML classifier as malicious, with ClamAV identifying it as Pdf.Phishing.Trojan. The file contains a large number of external links pointing to PDFs hosted on disposable domains, suggesting a link farm or phishing campaign. The embedded content, though heavily obfuscated, appears to be related to interview questions, a common lure for phishing.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://bologen.ru/123?utm_term=handling+conflict+interview+questions+and+answers PDF link annotation
    • https://wotopegajoxife.weebly.com/uploads/1/3/4/0/134042499/d193295cad189.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4402000/normal_605408b8777ae.pdfIn PDF document text
    • https://gidorimafemona.weebly.com/uploads/1/3/4/8/134867851/dirifowi.pdfIn PDF document text
    • https://fizegebukuri.weebly.com/uploads/1/3/1/4/131453213/1cf97f555e409d.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4408593/normal_601c944b1e61c.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4488815/normal_5fc73141310fd.pdfIn PDF document text
    • https://xepekozodixati.weebly.com/uploads/1/3/5/3/135346226/5493992.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4467589/normal_5fcccc0a5db2b.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4491432/normal_6050d31b18341.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4408989/normal_605246b7497fb.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4459645/normal_6010562b21ce1.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4473340/normal_604e18171e0ce.pdfIn PDF document text
    • https://gejekawuxo.weebly.com/uploads/1/3/4/4/134497426/768436d39d6581f.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4370072/normal_60074deb22aa6.pdfIn PDF document text
    • https://kigubesafikuva.weebly.com/uploads/1/3/4/8/134891874/1d774163.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4372682/normal_5ff6d5a62a1b6.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4488330/normal_603ebb9749c67.pdfIn PDF document text
    • https://jowapiwinutakun.weebly.com/uploads/1/3/4/3/134365581/davututo.pdfIn PDF document text
    • https://rejafolurolege.weebly.com/uploads/1/3/0/7/130740622/5076578.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4378628/normal_60534fd2ab1b8.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn 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_off0000f5fd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF5FD 5428 bytes
SHA-256: 56b0e5713521ec9fff627e8799ea8aa79f98ce68bff401f42c701c1074f92cbe
font_01_sfnt_off00010891.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10891 10432 bytes
SHA-256: bb1fbd686c9b875717c823a7a62d2f45767a6676d81564646746aa24af5e2d11