Malicious PDF — malware analysis report

Static analysis result for SHA-256 810874a126e4c434…

MALICIOUS

PDF

75.8 KB Created: 2021-07-04 01:23:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-13
MD5: 20bf0cf572dd502ab002f7b6c557fad3 SHA-1: 90460b9a4a7837dc5c85784823077abf2bff6585 SHA-256: 810874a126e4c434b41ceb180a6d195ba8fb8e537495f8d833ab3e78df5b148a
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF document functions as a link farm, directing users to various compromised websites that host malicious files. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution. Although no scripts were directly extracted, the presence of numerous links on compromised CMS upload storage and disposable hosting points to a coordinated effort to distribute malware, potentially via a PDF-based lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9840

Heuristics 7

  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://indiebookoftheday.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c8de48c8793---11268102464.pdf In PDF document text
    • https://agilitynd.com/wp-content/plugins/super-forms/uploads/php/files/e35073e5c249bae2556592a1fd4028ce/7379419059.pdfIn PDF document text
    • http://bergfin.se/wp-content/plugins/formcraft/file-upload/server/content/files/1609f32896fc28---kubovewenupebaped.pdfIn PDF document text
    • http://1970fchs50thclassreunion.com/clients/1/19/19770213778af891f1b13fa25f964f50/File/gurebatikojarisen.pdfIn PDF document text
    • https://www.potterycommercials.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1606ca40553e89---30805960956.pdfIn PDF document text
    • https://psystat.net/candyticket/uploads/page_images/files/8648278297.pdfIn PDF document text
    • http://barcelonasixtytwo.com/userfiles/file/11369077250.pdfIn PDF document text
    • https://nowbali.co.id/wp-content/plugins/formcraft/file-upload/server/content/files/16080a64386f82---jaramogevinujuvijomilag.pdfIn PDF document text
    • https://thehamptonsbloomington.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608940b572546---zovug.pdfIn PDF document text
    • https://misionesmedellin2030.com/wp-content/plugins/super-forms/uploads/php/files/oicqnpjr00mdur1e7n0ht75i38/pinatoxoz.pdfIn PDF document text
    • http://kahounova.cz/userfiles/file/3336892369.pdfIn PDF document text
    • https://www.hungarianassociation.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606fd16f4ec1d---joribiranizasuni.pdfIn PDF document text
    • http://andreevmag.com/wp-content/plugins/super-forms/uploads/php/files/1caeaceb337bfb604ad905317e24c4ce/separikegopofagaxobolix.pdfIn PDF document text
    • https://insights3.com/wp-content/plugins/super-forms/uploads/php/files/e9d22efd9ea588411e48307ff0fda889/pejisifamimilukurosix.pdfIn PDF document text
    • https://fietenhaardenenkachels.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1608af5bea6a8c---45554461067.pdfIn PDF document text
    • https://specialbrands.gr/wp-content/plugins/super-forms/uploads/php/files/91f9881d43e54a3dcc382b1ea3857e60/bomixixulirirebuji.pdfIn PDF document text
    • https://fermuar.com/wp-content/plugins/formcraft/file-upload/server/content/files/160de5b64e05f8---fimadixobamuduretonaf.pdfIn PDF document text
    • http://matsusushionline.com/uploads/files/saxixelogikus.pdfIn PDF document text
    • https://www.dazzlingdecor.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160aec372945e9---kikib.pdfIn PDF document text
    • http://securitydirect.it/wp-content/plugins/super-forms/uploads/php/files/6f0c1f01cbef519db24ee6a5253e8b12/zudemudoduxop.pdfIn PDF document text
    • https://maydongy.com/wp-content/plugins/super-forms/uploads/php/files/subamj68fjadape9pj97ndu8of/wavore.pdfIn PDF document text
    • https://fietenhaardenenkachels.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1609bc7ff36ce9---terekanudulurojemitupi.pdfIn PDF document text
    • https://drivingschoolofnorthtexas.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c66554de56e---8995688064.pdfIn PDF document text
    • https://gradeagroup.com/wp-content/plugins/super-forms/uploads/php/files/12h214nnb9udagf94detetlif1/xomes.pdfIn PDF document text
    • https://moscowfashion.net/content/xuploadimages/file/xapolabejibidixeg.pdfIn PDF document text
    • http://gwardiajuvenia.pl/zdjecia/fck/file/kokofalibeborumu.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/fzgW7-mxBc0/uplcv?utm_term=word+to+pdf+document+converter+free+downloadPDF 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_off0000c638.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC638 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000de4f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDE4F 10768 bytes
SHA-256: ca6e52834d20c1455ac24d81c611af220b8153af3751fe16bf192947e29eb54e
font_02_sfnt_off0000f725.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF725 16304 bytes
SHA-256: 802e503a8d77bde1755a07023cb7f81d2e1807bfb68d5effbe0261b473363e76