Malicious PDF — malware analysis report

Static analysis result for SHA-256 03a53819d96142de…

MALICIOUS

PDF

77.9 KB Created: 2021-09-16 05:11:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: c6ef08b33b7d56de526eda99fd0a384e SHA-1: 81ccf0a5561dad16c733689469dc0c7d1c7fb153 SHA-256: 03a53819d96142dedcfc6dbd3eb2c26347f6c74baf153160a3e4d2361037c80d
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.001 User Execution: Malicious Link

The PDF contains numerous links to external websites, many of which are hosted on compromised CMS platforms or disposable domains, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution. No scripts were extracted, but the structure and URL patterns are indicative of a malicious PDF.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9980

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://www.leesii.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613ebf2cc22de---sujozegaxabokugugog.pdf In PDF document text
    • http://shopcloud.cloud/ckfinder/userfiles/files/sixumadapikajavirodat.pdfIn PDF document text
    • http://midel.me/userfiles/file/38357980185.pdfIn PDF document text
    • http://dhleisure.com/ckupload/files/13820220065.pdfIn PDF document text
    • http://dlshixiang.com.cn/ckfinder/userfiles/files/31614003364.pdfIn PDF document text
    • http://sanraimundo.cl/dyn/uploads/file/92183548152.pdfIn PDF document text
    • http://napiarsaigh.com/images/velozesoxixuneli.pdfIn PDF document text
    • https://cottonweb.net/userfiles/file/gudafogo.pdfIn PDF document text
    • https://inprovitpuertorico.com/ckfinder/userfiles/files/kinobuz.pdfIn PDF document text
    • http://k1a.ru/images/files/file/41457348336.pdfIn PDF document text
    • https://dom4m.de/userfiles/files/nagudetevi.pdfIn PDF document text
    • https://miamivanservice.net/wp-content/plugins/formcraft/file-upload/server/content/files/16141752674024---dafifulasu.pdfIn PDF document text
    • http://svs-pm.com/wp-content/plugins/formcraft/file-upload/server/content/files/161354676f092c---kezevutikamumedon.pdfIn PDF document text
    • https://impariant-club.ru/wp-content/plugins/super-forms/uploads/php/files/e51b13b14e19855751d59fa9bf08dd32/52285162967.pdfIn PDF document text
    • https://www.lipca.com/ckfinder/userfiles/files/15369389851.pdfIn PDF document text
    • http://monkey-do.net/userfiles/file/gidolatikus.pdfIn PDF document text
    • http://writtenmail.com/upload_images/file/64236062462.pdfIn PDF document text
    • http://gesundezellen.de/neu/userfiles/file/palofowiboluzesi.pdfIn PDF document text
    • http://xn--sanitrprofi-p8a.ch/fckeditor/editor/images/file/20054393478.pdfIn PDF document text
    • http://www.miamiairportlimo.net/wp-content/plugins/formcraft/file-upload/server/content/files/1613ff64977613---32743750152.pdfIn PDF document text
    • http://suportti.com/wp-content/plugins/formcraft/file-upload/server/content/files/161339fa49304e---25733247249.pdfIn PDF document text
    • http://diversecityuk.com/userfiles/file/nefuvo.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1KS0DP0cxss/uplcv?utm_term=tone+poem+definitionPDF 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_off0000cb3f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCB3F 10148 bytes
SHA-256: 96f199023c1be91bd9569408efab804b04148681280c47026aefe9bcf00f2015
font_01_sfnt_off0000e1da.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE1DA 18420 bytes
SHA-256: 35b620c156c09ccb968755c7e0963132d92332ec232a34451690a11954373a68
font_02_sfnt_off000111f1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x111F1 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1