Malicious PDF — malware analysis report

Static analysis result for SHA-256 b21433ecedd25199…

MALICIOUS

PDF

90.6 KB Created: 2021-09-01 03:09:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 0780274e735f207b1ce9a2c3caea4a5b SHA-1: 167cc17ef2968319a4e06c67e77bcf9af79e061f SHA-256: b21433ecedd251999544e4e739503e1fe24e3f169daf6a8a32de3f871becf039
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

This PDF file was detected as malicious by ClamAV and an ML classifier. It contains a link farm pointing to multiple compromised WordPress sites, which in turn host other PDF files. These linked PDFs are likely designed to lure users into downloading further malicious content or engaging in phishing activities. The presence of numerous links on disposable hosting and the use of compromised CMS upload directories strongly indicate a malicious intent to distribute harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

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://cald-lighting.com/wp-content/plugins/super-forms/uploads/php/files/a3e8db60b17a42948d0b4e12b878b3ab/fafuja.pdf In PDF document text
    • https://laneopx.com/wp-content/plugins/formcraft/file-upload/server/content/files/160945755f04cb---wojapawanevixesusof.pdfIn PDF document text
    • http://www.victorian-manor.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160a479197465a---25977534767.pdfIn PDF document text
    • https://member-amz-seller-system.de/wp-content/plugins/super-forms/uploads/php/files/7709bd1b2d6c3e3babed8be9bd12a1ff/34524135361.pdfIn PDF document text
    • http://fittbike.hu/files/file/38260985946.pdfIn PDF document text
    • https://hram-uspeniya.ru/ckfinder/userfiles/files/28916259274.pdfIn PDF document text
    • http://dh-life.com/ckfinder/userfiles/files/95514508177.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ca7782decf6---909254218.pdfIn PDF document text
    • https://amezdigital.com/wp-content/plugins/super-forms/uploads/php/files/297a3bb315c806a7816f9517a3dc07e7/gavekidaninezal.pdfIn PDF document text
    • https://www.superioreagle.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607aaee416ed6---lijuxagituzovipebetib.pdfIn PDF document text
    • http://akvatoria.by/UserFiles/files/79000376807.pdfIn PDF document text
    • https://clubesolbra.com/uploads/files/ritufu.pdfIn PDF document text
    • http://anthonyvienna.com/sites/default/files/file/41408698580.pdfIn PDF document text
    • http://amako-ra.com/wp-content/plugins/super-forms/uploads/php/files/fc990a1b9d25dcf7e67f65458d811998/jolawuxukan.pdfIn PDF document text
    • https://ohcsi.com/ckfinder/userfiles/files/bukulonowosirafuwepokam.pdfIn PDF document text
    • http://www.tif.cn/wp-content/plugins/super-forms/uploads/php/files/tlbod0uukhrku10f0fu4tip8qb/bunuwelemugidazedufa.pdfIn PDF document text
    • https://perfecthospital.net/ckfinder/userfiles/files/kuwumufovelasotarime.pdfIn PDF document text
    • http://jarosi.hu/files/file/95240857217.pdfIn PDF document text
    • https://ncfouting.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607bda7090216---rozezewosewefowani.pdfIn PDF document text
    • http://enidental.com/userfiles/file/20210805005101.pdfIn PDF document text
    • https://formapolis.it/wp-content/plugins/super-forms/uploads/php/files/fc2b289327be34b3f1cc978ecd1ade26/jagasubelejejezip.pdfIn PDF document text
    • https://mertlakustika.cz/images/pages/file/kerinojifewupokigegizilu.pdfIn PDF document text
    • http://energosol.pl/images_cms/file/wonetawewofun.pdfIn PDF document text
    • http://kledingindex.nl/images/uploads/verepixu.pdfIn PDF document text
    • https://venefoil.com/ckfinder/userfiles/files/95005694797.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3vuEKuznOb8/uplcv?utm_term=learn+old+english+with+leofwin+pdfPDF 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_off0000f129.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF129 10820 bytes
SHA-256: c8ef2a080000077e6857d1e472d099d08190aff92032d5c9e39d114c84d3823d
font_01_sfnt_off000109da.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x109DA 22052 bytes
SHA-256: 444aea1804a710a214bffa702e06787e3093759a7d819b0d9395fef3eb02b19a
font_02_sfnt_off000143cb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x143CB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1