Malicious PDF — malware analysis report

Static analysis result for SHA-256 a39af8fff953c7d8…

MALICIOUS

PDF

71.7 KB Created: 2021-06-08 05:33:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-25
MD5: c836ee6436adfc005071acad1af8ebe2 SHA-1: e77c307f6f8e404b7d7ce080dbbd852d053350d1 SHA-256: a39af8fff953c7d82ef587cb40cc2065f5b420c6405c614c2bdb1f60eb91200d
126 Risk Score

Malware Insights

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

The sample is identified as malicious by ClamAV and an ML classifier, indicating it's a phishing attempt. The PDF contains numerous embedded URLs, with one prominent URL pointing to a link farm designed to redirect users. The document body, though heavily obfuscated, appears to be a lure related to a 'study bible'. No scripts were extracted from this sample, but the presence of multiple external URIs and the link farm heuristic strongly suggest a phishing or redirection attack.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

Heuristics 5

  • 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 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://coretry.ru/pbw?utm_term=niv+scofield+study+bible+large+print PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4492600/normal_5fd9a22e38bfe.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4467007/normal_605fd46f1dcad.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4478148/normal_6029df33bbfa4.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4412195/normal_5ff87f10b9f1b.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4528915/normal_6037000833ae6.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4374951/normal_6047b7c2dd262.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4408709/normal_6048a224bcf2c.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4403266/normal_6030cac73767c.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4463554/normal_5fd97566bd06b.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4479684/normal_606cc5f86babf.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4393762/normal_5feeae00621ca.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4384310/normal_603f0e91d2fc5.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://xulajirose.pbworks.com/w/file/fetch/144832341/why_did_macbeth_kill_duncan_offstage.pdfIn PDF document text
    • http://fatakalewene.pbworks.com/f/3974740347.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/118ad3be-6423-4f6f-a17a-62925f9dd0c6/what_does_a_medical_lawyer_do.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/7fda1475-7390-4f5c-8efd-25d679b6a097/fodipose.pdfIn PDF document text
    • http://depowota.pbworks.com/f/31082822141.pdfIn PDF document text
    • http://pakesobiroge.pbworks.com/w/file/fetch/144697425/to_kill_a_mockingbird_symbolism_worksheet_answers.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/0dc5e29a-3b9f-40ec-9925-ad9f39cd4a6f/wusiximemixixevarakudugu.pdfIn PDF document text
    • http://taxexuwej.pbworks.com/w/file/fetch/144431295/bineriwawog.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/12b651b0-a782-4d64-a6b3-64a9f6cd1666/will_personal_credit_affect_business_credit.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/db77f431-5c7c-4c15-9540-dd9f60f41f83/child_support_for_50_50_custody_canada.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_off0000d9a4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD9A4 5596 bytes
SHA-256: 65791a1a451b9d1cb34534d899d6d4a322179199d959c345afb90485d8a9238a
font_01_sfnt_off0000eccc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xECCC 10920 bytes
SHA-256: 10950339c44dc3a85371e8304a73e583917d7c78c4fb93d6655fb57151fe5bb2