Malicious PDF — malware analysis report

Static analysis result for SHA-256 b93cb221d4247635…

MALICIOUS

PDF

68.6 KB Created: 2021-09-15 21:34:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 1e15d8558b0632fedf4bfb843ccfb4be SHA-1: ba81621d5e9f9f030b32de3622ee1ffebf7cb730 SHA-256: b93cb221d4247635e6447a41dad85a0c01ce7ab0a9f222e00378e446f8f069ea
146 Risk Score

Malware Insights

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

The PDF was identified as malicious by ClamAV and an ML classifier, exhibiting characteristics of a phishing lure. Heuristics indicate it's an image-only document with a click-outward action, typical of a screenshot lure. Numerous external URIs were found, many hosted on disposable domains, suggesting a link farm used to distribute malicious content or redirect users to phishing sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9965

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
  • Image-only document with action trigger (screenshot lure) medium PDF_IMAGE_LURE
    PDF has 1 image(s), only 1 text block(s), carries a click-outward action, and is only 68 KB — typical shape of a phishing lure where a full-page screenshot hides a clickable button that launches or submits to an attacker URL.
  • 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://crysiq.ru/uplcv?utm_term=house+of+fun+free+coins+2017 PDF link annotation
    • https://cafesca.info/ckfinder/userfiles/files/94650100048.pdfIn PDF document text
    • http://yuanhebiotech.com/upload/files/57108205883.pdfIn PDF document text
    • http://sujitonweb.com/userfiles/files/48439037189.pdfIn PDF document text
    • https://tebra.si/userfiles/file/82654062147.pdfIn PDF document text
    • https://www.renfrewareahealthvillage.ca/ckfinder/userfiles/files/bikemilo.pdfIn PDF document text
    • https://bearings.vn/images/ckeditor/files/22649846616.pdfIn PDF document text
    • http://posicert.com/upload_fck/file/2021-9-4/20210904170833919586.pdfIn PDF document text
    • https://espiber.cl/images/uploadedimages/file/dopewepujixekebamiv.pdfIn PDF document text
    • http://czminghe.com/upload/files/43673941120.pdfIn PDF document text
    • https://2b3la571ga-70p.com/contents/files/53829056242.pdfIn PDF document text
    • http://kanalizace-ul.cz/userfiles/file/64583162659.pdfIn PDF document text
    • http://www.europesolidaire.eu/userfiles/files/jusugilekunatekamebi.pdfIn PDF document text
    • http://businessdevelopmentcenter.pl/uploads/userfiles/files/94826905156.pdfIn PDF document text
    • http://stopasbestos.ca/wp-content/plugins/formcraft/file-upload/server/content/files/161391588e18e0---xixob.pdfIn PDF document text
    • http://wwstationery.com/files/file/wizofurarirelejuvupofed.pdfIn PDF document text
    • http://hycxchina.com/filespath/files/20210903155656.pdfIn PDF document text
    • http://furnitura-syndicat.ru/ckeditor/ckfinder/core/connector/php/uploads/files/7770027052.pdfIn PDF document text
    • http://wo-kop.pl/userfiles/file/binavaxorobo.pdfIn PDF document text
    • http://spbmedax.ru/sites/default/files/uploads/96219578296.pdfIn PDF document text
    • http://sineadstone.com/userfiles/file/85951057569.pdfIn PDF document text
    • http://sbcnepal.com/images/file/39993705434.pdfIn PDF document text
    • http://coinproject.com/userfiles/image/file/86161778144.pdfIn PDF document text
    • https://laughteronlineuniversity.com/images/upload/files/27483721217.pdfIn PDF document text
    • http://chapaconoticias.com/assets/ckfinder/core/connector/php/uploads/files/nuribulexegepumoteki.pdfIn PDF document text
    • http://rivebistro.net/ckfinder/userfiles/files/96734446472.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://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_off0000b22d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB22D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ca44.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCA44 10460 bytes
SHA-256: 30c1aa511c30bfa1e37bed4f2e2d2af61f5300bc022e9dba0997b417e0ccbc2c
font_02_sfnt_off0000e239.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE239 14164 bytes
SHA-256: 7f8d77530e7586a977752ea8cc731f7bb3e44482da5327b9cc02d29fd176e246