Malicious PDF — malware analysis report

Static analysis result for SHA-256 d78aad7b98fb3364…

MALICIOUS

PDF

74.2 KB Created: 2021-09-26 12:27:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: f421809d60710e97f92fbbc79a81c9dc SHA-1: 301fa1130939706c8c7301c164ea02af1af3a435 SHA-256: d78aad7b98fb336456c9d0f4ced3064d0a6f7c4a5c38c5c52d4ea8dc0554b8cc
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains numerous embedded URLs, many of which point to PDF files hosted on various domains. Heuristics indicate this is a link farm, with some URLs pointing to compromised CMS upload storage. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware delivery through these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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://nmg.lv/img/uploads/files/27405556716.pdf In PDF document text
    • https://palet-school.com/files/files/28075419274.pdfIn PDF document text
    • https://nikosdimos.gr/userfiles/file/63666689052.pdfIn PDF document text
    • http://architectureanddesign.it/userfiles/files/benisif.pdfIn PDF document text
    • https://honghow.com/ckfinder/userfiles/files/fogadiruzixem.pdfIn PDF document text
    • http://amtusa.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613882f9abdf5---jisedixusokekuzetizati.pdfIn PDF document text
    • http://nature-revive.org/files/file/batemutiwemor.pdfIn PDF document text
    • http://www.191seo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613fa2ffbdfdf---55948144298.pdfIn PDF document text
    • https://stcc-sa.com/motakamel/Ups/files/56912413624.pdfIn PDF document text
    • http://ulrike-mayer.de/userfiles/files/95625214003.pdfIn PDF document text
    • https://www.hosotte.com/ckfinder/userfiles/files/64524728158.pdfIn PDF document text
    • https://inchirierielicopter.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1614ae141e1a28---serojimep.pdfIn PDF document text
    • https://ariaparvaz.com/basefile/ariaparvazcom/files/duxagobamezomowipov.pdfIn PDF document text
    • http://www.tecnobor.es/ckfinder/userfiles/files/62043417188.pdfIn PDF document text
    • http://findacommodity.com/upload/file/95953463921.pdfIn PDF document text
    • http://toanthinh.vn/webroot/img/files/9652526048.pdfIn PDF document text
    • https://gestionarival.com/userfiles/file/jowetuduxazalabibe.pdfIn PDF document text
    • https://joepromenshealth.com/wp-content/plugins/super-forms/uploads/php/files/3e0498d1fe7483f2c5b8e0c20d33539f/dopudalaromomakomo.pdfIn PDF document text
    • http://teplolux72.ru/upload/file/kesakajenebalobomorevolok.pdfIn PDF document text
    • http://erkerlaender.de/wp-content/plugins/formcraft/file-upload/server/content/files/1614b45ae6c8ad---69306324120.pdfIn PDF document text
    • http://fbrasil.com/userfiles/file///79612508046.pdfIn PDF document text
    • http://meimagedance.tw/ufiles/files/4853153668.pdfIn PDF document text
    • http://bortran.com/upload/image/file/20210916111304.pdfIn PDF document text
    • https://biogenetixpharma.com/ci/userfiles/files/67041190592.pdfIn PDF document text
    • http://fullx.net/files/2246367740.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/ngfLrbzwjls/uplcv?utm_term=shareit+old+version+for+android+4.0+4PDF link annotation
    • 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://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ba46.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBA46 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d258.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD258 17632 bytes
SHA-256: e472478cdcb8469c2c52b82eee377f580f30996f6f69534a7c8c166fd66dfc2b
font_02_sfnt_off0001000a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1000A 10856 bytes
SHA-256: 9d65f6c30e157f987b74fe2645cadfa1556972f1f90375a5193a05c75a5cccca