Malicious PDF — malware analysis report

Static analysis result for SHA-256 78ad63a46b887e97…

MALICIOUS

PDF

76.3 KB Created: 2021-03-09 16:33:00 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-22
MD5: c4c3e895b0781d28f2921f0051f9c42b SHA-1: 9171beb19075b59402ce8a3b941611ba9cd2bf97 SHA-256: 78ad63a46b887e97696d28e4c0036867e5a673a76a9c8bf5f6256161ac30b28e
226 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. It uses a password-protected-archive lure. 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 0.9998

Heuristics 7

  • 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.
  • Password-protected archive handoff high SE_PASSWORD_ARCHIVE_LURE
    Document gives password instructions for an archive or attachment — often used to keep payloads encrypted until after gateway scanning
  • 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://zajinet.ru/strik?utm_term=us+army+drill+sergeant+campaign+hat PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4498404/normal_600c876842903.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4424331/normal_600183b346540.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4464523/normal_5fd6d9b899b93.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4422643/normal_6045deb539ae0.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/8e5ce81e-edcd-43a9-8ccf-08f2e54b4bd1/history_alive_the_ancient_world_chapter_19.pdfIn PDF document text
    • https://1ac5d900-0c69-4f12-8b1d-4e209472b8d2.filesusr.com/ugd/828753_9a5626e2f8ab4f2cafba6dbed8930fec.pdf?index=trueIn PDF document text
    • https://07d68bf2-0661-47e2-9ffe-eae068a071af.filesusr.com/ugd/fef806_dd2a03b77bf84b829d078a6fc65e27bb.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/juvosi/1118526781.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/04511209-23b0-42c3-b5d8-a8d5e9ab11b1/lomitanit.pdfIn PDF document text
    • https://5a1138df-423b-4a5d-a7c7-36223740754e.filesusr.com/ugd/a72fa8_d63c5a482529420c9563a24555ac19b7.pdf?index=trueIn PDF document text
    • https://911f1565-2faa-4874-b261-330d521e7362.filesusr.com/ugd/f46427_c575fe379cb24d86bd95a21a0c692a18.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/sisaxu/bazimuzi.pdfIn PDF document text
    • https://ad9e3d1f-bb22-46ca-892e-b6aa3325a756.filesusr.com/ugd/837d34_06333b1ff2e94fa58667d6f1f785a9a2.pdf?index=trueIn PDF document text
    • https://df256b98-640c-444d-885a-8195c7360722.filesusr.com/ugd/40b9e6_2225298b1ee34c21bab5577ca026f596.pdf?index=trueIn PDF document text
    • https://c2267750-1f6d-4c2f-944a-eb302c7f07d7.filesusr.com/ugd/93971e_801ba1b142304590995635f29d3c3702.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/lowuwofuxali/canon_inkjet_mx700_driver.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/0095b4ff-f08d-469b-abcc-04af2381f280/76976769697.pdfIn PDF document text
    • https://s3.amazonaws.com/fewifuwu/crystal_reports_runtime_server_2016.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_off0000edc9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEDC9 5580 bytes
SHA-256: 797b11e7d215db71710aa59080fb45e35bcff5827e9e4418b7036cb7573e2688
font_01_sfnt_off000100a2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x100A2 10396 bytes
SHA-256: 17a61e5c92dc85f6b247f23e1f56b99fb93d955717f6f90f69606c8f1f94fcf3