Malicious PDF — malware analysis report

Static analysis result for SHA-256 a1b5265ed24dfcfc…

MALICIOUS

PDF

81.1 KB Created: 2021-09-17 02:34:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: d2ecea0ed42aca4e56c3d1f0e6f1f6ca SHA-1: b1551474ff3c9ca5f761959886bf4a771832a34c SHA-256: a1b5265ed24dfcfc66e2d1d30596f3b7882ebfcc28f2f6f500341a606ad20915
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a link farm pointing to various PDF files hosted on potentially compromised websites, with one URL explicitly mentioning 'download adobe flash player'. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware distribution. No scripts were extracted, but the structure suggests a lure to download a malicious payload.

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://mbbs.hr/files/bejupikozitirupumeg.pdf In PDF document text
    • http://hitplus.eu/userfiles/file/38682841057.pdfIn PDF document text
    • https://doanandieuduong295doson.vn/namthuan/images/news/files/39586153660.pdfIn PDF document text
    • http://mikol-styl.cz/userfiles/file/jugukineka.pdfIn PDF document text
    • http://travelport.pl/userfiles/file/6772734370.pdfIn PDF document text
    • https://open-call.fr/uploaded/files/xebonuwisedutib.pdfIn PDF document text
    • http://nifaelectronics.com/userfiles/file/jawejonajutinotilevif.pdfIn PDF document text
    • https://mobilaide.com/upload/editor/file/67021464792.pdfIn PDF document text
    • http://rdmsrl.it/userfiles/files/mukegemubapejisiwumenuza.pdfIn PDF document text
    • http://blevy.com/ckfinder/userfiles/files/xodafajoxa.pdfIn PDF document text
    • https://legacydockandmarine.com/wp-content/plugins/super-forms/uploads/php/files/2f64f43e4e07a6c088634154a1b9d2de/9304606575.pdfIn PDF document text
    • http://a-range.ru/wp-content/plugins/formcraft/file-upload/server/content/files/161306ff934de3---31950184156.pdfIn PDF document text
    • http://cafemsoffice.com/userfiles/files/68651566939.pdfIn PDF document text
    • http://radio-salsa.fr/php/rs/filesupload/file/67604083741.pdfIn PDF document text
    • http://lingvastar.z-i-g-z-a-g.com/userfiles/files/lanunogo.pdfIn PDF document text
    • https://hgb.se/filer/file/sajarirej.pdfIn PDF document text
    • http://daithanhnam.com/upload/files/1290479519.pdfIn PDF document text
    • http://imhkayseri.com/resimler/files/3428373937.pdfIn PDF document text
    • http://quatanggiabao.com/images/uploads/files/16222013479.pdfIn PDF document text
    • https://totalyoumovement.com/wp-content/plugins/formcraft/file-upload/server/content/files/16131425fe686d---34651980998.pdfIn PDF document text
    • https://suacuacuontoanphat.com/upload/files/89143766306.pdfIn PDF document text
    • http://eegbiofeedback-leszno.pl/userfiles/file/liwaropukevorusev.pdfIn PDF document text
    • http://xlpe.net/Images_upload/files/zoriga.pdfIn PDF document text
    • http://wimborst-ceramics.nl/public/view/upload/fckeditor_images/file/42128814444.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/cv9VXjIrmdE/uplcv?utm_term=download+adobe+flash+player+11+for+androidPDF 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_off0000d834.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD834 17492 bytes
SHA-256: 7bda935284e311ca1702b5a20b3861b5ba5bf4a343021a9aef9101a8b468a0d5
font_01_sfnt_off00010557.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10557 10888 bytes
SHA-256: f115238a8c537ca7b7a488db4bd348bbdb1e4d5acd8c4e2b9b0afbeab245a4db
font_02_sfnt_off00011e52.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11E52 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1