Malicious PDF — malware analysis report

Static analysis result for SHA-256 973fd725b41f3e91…

MALICIOUS

PDF

77.2 KB Created: 2021-06-10 02:30:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-29
MD5: 0fff18ac7548bebf76221c12f35d0b2d SHA-1: 547c8601a7c8c725c902d038b89df046d01cf69c SHA-256: 973fd725b41f3e91763fd5373be651d0a292382fb7ff15893214b77cfbe396b2
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 pointing to disposable hosting services, indicating a link farm designed to direct users to potentially malicious content. The ClamAV detection and ML classifier strongly suggest a phishing or trojan payload is intended. While no scripts were explicitly extracted, the PDF structure and link farm behavior are indicative of a phishing lure, likely delivered as a spearphishing attachment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://nomylo.ru/pbw?utm_term=friends+quiz+20+questions+and+answers PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4393752/normal_5fdc60ce58fe0.pdfIn PDF document text
    • https://sozumibazukupiv.weebly.com/uploads/1/3/4/7/134735026/40878e4a388b.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4500001/normal_5ff1aef22b49e.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4416671/normal_6024f38dabc62.pdfIn PDF document text
    • https://dobopekajami.weebly.com/uploads/1/3/4/3/134314215/8348781.pdfIn PDF document text
    • https://xukonupuzifig.weebly.com/uploads/1/3/4/6/134621954/pufavogow.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4367665/normal_602f5f7797ca6.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4375509/normal_5febe38febce9.pdfIn PDF document text
    • https://pibazafefudo.weebly.com/uploads/1/3/0/7/130776509/984ca34ed.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4423428/normal_60c0e8147e763.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4411252/normal_6061297f55109.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4382189/normal_600d24f685ac2.pdfIn PDF document text
    • https://vozuviwugil.weebly.com/uploads/1/3/2/6/132681927/4967686.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/0f7f653e-8119-4982-858a-93abdf8ced38/how_to_read_tarot_cards_for_beginners_book.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/c6e3080a-0d73-436a-8c06-70d0221b0b9e/35478108325.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/627cba48-7beb-4750-a9af-a5c7a57d50ee/65786729028.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/809433b7-8f25-435c-b055-6a752d45b777/ms_driver_license_renewal_documents.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/cf5c85fe-f936-464b-925b-27192d32fba0/40577143820.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/788f88f7-3380-44d8-8951-7aa00110aebe/30609667579.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/8d60055b-7d07-4e39-af82-73628a347d58/wedgewood_vision_stove_manual.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_off0000f08a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF08A 5284 bytes
SHA-256: 0c9d6fb8cc25bf4c0bd1759bc3c770a2d96b8a2ea57b61eb558b2558b4e6ba20
font_01_sfnt_off000102a6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x102A6 10896 bytes
SHA-256: cefc9cf007c9097a0cff6c5ad112980e693f202d5cc594a70a94c363f9beb8fd