Malicious PDF — malware analysis report

Static analysis result for SHA-256 a7ff8294524344c6…

MALICIOUS

PDF

98.7 KB Created: 2021-03-09 02:56:49 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-05-22
MD5: 7f637c9f5ab61a26a08968bd0e38bd90 SHA-1: d263e44ed478ccb66e2a80913964afe7d79aeb7a SHA-256: a7ff8294524344c6e44969026646063df15e40f06e6cf84d568e9064b22ad366
186 Risk Score

Malware Insights

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

The PDF contains a link farm designed to redirect users to various other PDF documents, masquerading as a free download. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware distribution. The embedded URLs and the PDF structure suggest an attempt to generate traffic and potentially deliver further payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

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://leonvi.ru/strik?utm_term=delavier%2527s+core+training+anatomy+pdf+free+download PDF link annotation
    • https://cdn.sqhk.co/vefomatakin/iePiajc/tewesokotepubij.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4501484/normal_600baad243e49.pdfIn PDF document text
    • https://cdn.sqhk.co/wevexifimur/fhfjemh/new_york_times_puzzle_books.pdfIn PDF document text
    • https://cdn.sqhk.co/torixugajo/ibSa6Xv/44206283841.pdfIn PDF document text
    • https://cdn.sqhk.co/nowavutu/gjUjcAa/fivujoxozami.pdfIn PDF document text
    • https://cdn.sqhk.co/lunosupi/if9f0ic/yellowstone_season_3_episode_8_cast.pdfIn PDF document text
    • http://gebatuvarak.66ghz.com/zutabefatuzol.pdfIn PDF document text
    • https://cdn.sqhk.co/womawuxinuge/90Ric8T/15084014943.pdfIn PDF document text
    • https://cdn.sqhk.co/guwezasov/fhehcnD/regibevikejafileduwixi.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4403819/normal_6021e83debc3b.pdfIn PDF document text
    • https://cdn.sqhk.co/vasibejovej/9jgjjjc/verizon_wireless_smart_family_premium.pdfIn PDF document text
    • http://naziniza.22web.org/eso_maelstrom_arena_guide_sorcerer.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • https://9849c7ec-8b19-4b81-9a64-db2537ea7c40.filesusr.com/ugd/97b1c0_270531d685db443d8375b60ddbf3fcad.pdf?index=trueIn PDF document text
    • https://711920be-b761-4f0e-a604-762b26663b16.filesusr.com/ugd/ffcbea_ec7d276254d84acaa4a534c50b9bc21e.pdf?index=trueIn PDF document text
    • http://kenuzuwemonuda.epizy.com/66638544081.pdfIn PDF document text
    • http://merizipu.rf.gd/dunkin_donuts_cake_donut_calories.pdfIn PDF document text
    • https://336ddc11-c37d-4cd6-9685-7accad2975f7.filesusr.com/ugd/479fa9_1cc4eda8419640f5885ba361d1376cd8.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/1a6e03da-017a-4f8f-8e56-fe404eb72f00/letewupufava.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/278342bc-913b-470b-87e7-8e1351e062db/what_a_2nd_grader_needs_to_know.pdfIn PDF document text
    • https://12c48f50-3553-44c7-a31c-19fc5df83d07.filesusr.com/ugd/7e0eb0_efab0fc6ac8943f5a61e45ae155b6648.pdf?index=trueIn PDF document text
    • http://zekovulelopur.epizy.com/academic_writing_guide_utas.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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0001340a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1340A 5552 bytes
SHA-256: 470b2846028eddad6e6690580b1af33fcf3eac014f6e34c2bf5144a6744b9f7a
font_01_sfnt_off000146f7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x146F7 11892 bytes
SHA-256: 0cb1faec4475682c0b428c3bd1a701cacaaf35acbd202eed514e34f67c9ef86c
font_02_sfnt_off00016ec5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x16EC5 4324 bytes
SHA-256: b50a2106bf82917db0cd3cf88f63c5e8cc3298b343ace5cffc591b35df33d24c