Malicious PDF — malware analysis report

Static analysis result for SHA-256 a9a0c7a44b062de8…

MALICIOUS

PDF

68.7 KB Created: 2021-09-18 13:56:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 43e22aa9b175bb8a714560af89029e21 SHA-1: 4bd33afab0d1bb9f3a60821b3e955e664bf51a50 SHA-256: a9a0c7a44b062de86f61d6bb66406358b99683645c1211475d9572c9c9f5c1b1
156 Risk Score

Malware Insights

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

The PDF was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing or trojan. Heuristics indicate it functions as a link farm, with many embedded URLs pointing to potentially compromised WordPress sites or disposable hosting. The primary purpose appears to be directing users to external malicious content, likely for phishing or further malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9837

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
  • 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 http://lavalnerina.com/userfiles/file/vativovi.pdf In PDF document text
    • https://gpuhub.net/wp-content/plugins/super-forms/uploads/php/files/tdtso60791k22mndhid2fnce4v/mofojatenoxu.pdfIn PDF document text
    • http://namkhoabacninh.com/images/files/36877286504.pdfIn PDF document text
    • http://www.smpnuenen.nl/images/files/ronir.pdfIn PDF document text
    • http://www.skup.it/wp-content/plugins/formcraft/file-upload/server/content/files/1614017960a7ca---dojijosebewiwi.pdfIn PDF document text
    • http://roosprommenschenckelfoundation.nl/userfiles/file/davapozamod.pdfIn PDF document text
    • http://goldstecq.com/userfiles/file/13887940981.pdfIn PDF document text
    • http://ha-sine.com/d/files/94022742140.pdfIn PDF document text
    • http://hoachattn.com/image/files/74023053552.pdfIn PDF document text
    • https://oncallanatomist.org/ckfinder/userfiles/files/fijotobexemipovobego.pdfIn PDF document text
    • https://www.hdcorp.com.br/wp-content/plugins/super-forms/uploads/php/files/q63lo6dmiq1ao9ii58p8d4ogbc/kunofekimubajejug.pdfIn PDF document text
    • https://stdtekstil.com/upload/ckfinder/files/3388801205.pdfIn PDF document text
    • https://www.edm-medical.net/ckfinder/userfiles/files/lemikogovufu.pdfIn PDF document text
    • https://fu-ko-property-agency.com/webroot/editor-uploads/files/96008024338.pdfIn PDF document text
    • http://lsphc.com/userfiles/file///71304864477.pdfIn PDF document text
    • http://buydecor.ru/uploads/files/mewoxuma.pdfIn PDF document text
    • http://yuanhebiotech.com/upload/files/sisedonizorilarafesaf.pdfIn PDF document text
    • http://efeteknikyapi.com/userfiles/files/6526007157.pdfIn PDF document text
    • http://ebrinteractive.com/userfiles/file/newozijuxufimamazajin.pdfIn PDF document text
    • http://mega-gold.com/userfiles/files/gilagupadizedefevute.pdfIn PDF document text
    • http://accessiblevehicleservices.com/userfiles/file/gasobafamutaxovanapimo.pdfIn PDF document text
    • https://www.ediliziaindustriale.com/wp-content/plugins/formcraft/file-upload/server/content/files/161308d1109871---1655819968.pdfIn PDF document text
    • http://amandatravel.com/userfiles/file/83566577355.pdfIn PDF document text
    • https://khanoomhoteli.com/basefile/khanoomhotelicom/files/3040805338.pdfIn PDF document text
    • http://toyotarent.tw/FileData/ckfinder/files/20210902_BCD9ACACABB9469A.pdfIn PDF document text
    • http://tsyrulnikov.ru/upload/file/dimalufevepilofokekad.pdfIn PDF document text
    • http://hanasushichoice.com/uploads/files/vivinu.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/6naE_Nh8_CY/uplcv?utm_term=ios+ome+tvPDF 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_off0000b382.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB382 14628 bytes
SHA-256: 8894ed33c1c3f91272390ab721dc7630558686a7ee6eccf6bbfda0f6d76b7a11
font_01_sfnt_off0000d7e0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD7E0 9780 bytes
SHA-256: 8e4abeef4bc56e5303cd7d8fd2681e31e2596ae59b80d3377dfd3bc39938c01b
font_02_sfnt_off0000ed5d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED5D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1