Malicious PDF — malware analysis report

Static analysis result for SHA-256 ff23620525fc72c6…

MALICIOUS

PDF

80.1 KB Created: 2021-09-17 18:53:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 1117644de1ed03f3e54d16c72ccc3233 SHA-1: 6fc11d406b438393fa34ccc8f7e0dfdb3cf02039 SHA-256: ff23620525fc72c6c8721c8e53ada0e4014f4ca709cdcbc6ebad3e7f2e3c90fb
156 Risk Score

Malware Insights

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

The PDF contains a large number of links, many of which point to compromised WordPress sites. The 'PDF_SEO_DISPOSABLE_LINK_FARM' and 'PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM' heuristics indicate this is likely an attempt to manipulate search engine rankings or direct users to malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9846

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://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613f2d26086a6---niwizefeku.pdf In PDF document text
    • http://fs-select.com/images/blog/file/ruzevipubiragakuxutakad.pdfIn PDF document text
    • http://gemwishrs.com/ckfinder/stones/files/28410539572.pdfIn PDF document text
    • http://onsijsselstein.nl/userfiles/files/pibipavozatubizawikuxik.pdfIn PDF document text
    • https://igraonica.me/userfiles/file/zenunovaxuxuzifosa.pdfIn PDF document text
    • http://goldia.cz/data/file/69963345204.pdfIn PDF document text
    • http://gongotour.com/FileData/ckfinder/files/20210908_647AD497D41BB2D0.pdfIn PDF document text
    • https://dubaimotorcycletours.com/uploaded_images/files/16498544835.pdfIn PDF document text
    • https://springkasteelhuren.be/userfiles/file/75102856954.pdfIn PDF document text
    • https://www.helpagesl.org/wp-content/plugins/formcraft/file-upload/server/content/files/1613c0dd537c32---tupam.pdfIn PDF document text
    • http://studiorapizza.it/userfiles/files/13918792156.pdfIn PDF document text
    • http://rosabaum.de/web/editor/files/37737992598.pdfIn PDF document text
    • https://ourcampuswindow.com/ckfinder/userfiles/files/16407638744.pdfIn PDF document text
    • https://lenaoyunlar.net/calisma2/files/uploads/jemafep.pdfIn PDF document text
    • https://www.tcf.gov.tr/ckfinder/userfiles/files/21145241999.pdfIn PDF document text
    • https://tselectromechanical.com/uploads/CKfiles/files/31923111962.pdfIn PDF document text
    • https://gaadalagi.com/contents/files/27224750855.pdfIn PDF document text
    • http://sampoernastrategic.com/uploads/image/files/vaxugobukagorasisaji.pdfIn PDF document text
    • http://jumpinfit.it/userfiles/files/66477586288.pdfIn PDF document text
    • http://yuhao-tech.com/userfiles/file/bitixikipasog.pdfIn PDF document text
    • https://petroblend.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612ffdb22ba90---refure.pdfIn PDF document text
    • https://metnar.pl/web/uploads/files/mevubepikuranekez.pdfIn PDF document text
    • https://veritiesinstitute.com/wp-content/plugins/super-forms/uploads/php/files/3bfe4f99cf8d4a7912ec5be2cbfb7aee/54348288803.pdfIn PDF document text
    • https://semot.com/Store/userfiles/file/25426790957.pdfIn PDF document text
    • http://mosjob.ru/images/file/12109383599.pdfIn PDF document text
    • https://impulsa.mantareys.net/uploads/plantillas/files/rawani.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/PmAiG5ZyT-k/uplcv?utm_term=unturned+id+portable+generatorPDF 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_off0000d704.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD704 17060 bytes
SHA-256: c3887d0d10c483bcd84316528e430337e6293a6d80e9e90057e78b4f9049e933
font_01_sfnt_off000102e9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x102E9 10648 bytes
SHA-256: 204b17bb9e85a562bb60881be08a2f7105eebb1f736eef063fc9df84bbf5a1ed
font_02_sfnt_off00011ae8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11AE8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1