Malicious PDF — malware analysis report

Static analysis result for SHA-256 8b94f7d3a7b0dbc6…

MALICIOUS

PDF

74.7 KB Created: 2021-10-04 07:08:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 161b046ea6dff0b3923906485ac6e7bb SHA-1: 26f5a22ddd8ab79e95eeb92af84210e8d53281d7 SHA-256: 8b94f7d3a7b0dbc65d339dc69404f9bac381998d718c74361b276bd7f0da272d
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to disposable hosting or compromised CMS upload storage, indicative of a link farm designed to distribute malicious content or phish users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware delivery. No scripts were extracted, and the document body was unreadable, so the attack pattern is inferred from the URL heuristics.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

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://sieuthicayxanh.vn/webroot/img/files/tusovane.pdf In PDF document text
    • http://happinessgown.com/upload/users/files/piwapodazokusezovazoma.pdfIn PDF document text
    • http://songhakbbq.com/uploads/files/75701316714.pdfIn PDF document text
    • http://milkexim.ru/imgeditor/file/balojixapifegusolarizax.pdfIn PDF document text
    • https://chsromania.managenet.ro/images/file/sozutiweromipobafutexim.pdfIn PDF document text
    • https://madeinstlucia.com/userfiles/files/66360990484.pdfIn PDF document text
    • https://rtaadmin.mrv-educationservices.com/content_file/files/8866994729.pdfIn PDF document text
    • https://bold-iot.com/uploads/files/202110020915168861.pdfIn PDF document text
    • http://lexprikson.com/admin/style/images/userfiles/file/dirafivudasuzev.pdfIn PDF document text
    • https://pulsekb.ru/admin/ckfinder/userfiles/files/fuxewumudunitibefi.pdfIn PDF document text
    • http://zentrumok.com/userfile/files/welifokuvozar.pdfIn PDF document text
    • http://nakajima-ya.com/user_data/image/file/39142571529.pdfIn PDF document text
    • http://lisaarkin.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/65770340711.pdfIn PDF document text
    • https://www.landalastadservice.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613eb9321829c---94806916981.pdfIn PDF document text
    • https://www.marthatrotts.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1613de88384f2c---82749613384.pdfIn PDF document text
    • http://hasadtemizlik.com/upload/file/lejidakexi.pdfIn PDF document text
    • https://newshieldinsurance.com/demo/gsa/final/images/file/xedulanaf.pdfIn PDF document text
    • http://saiprogetti.net/userfiles/files/10924882838.pdfIn PDF document text
    • https://karapinler.com/calisma2/files/uploads/sitisar.pdfIn PDF document text
    • https://www.alapan.org/fckimages/file/81267146003.pdfIn PDF document text
    • http://kiszelyugyvediiroda.hu/docs/file/46628649365.pdfIn PDF document text
    • https://alenakovalchuk.ru/wp-content/plugins/super-forms/uploads/php/files/0709d90d24b8ad4173726734b9f02f29/64506036322.pdfIn PDF document text
    • http://enslev-anlaegsservice.dk/userfiles/file/ronuwibozivoxamo.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/PmAiG5ZyT-k/uplcv?utm_term=format+sd+card+recovery+apkPDF 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_off0000b976.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB976 18828 bytes
SHA-256: 7a346e474ce6bd33327489531cd0380d3e70f432044e81c6c7ca401be62a47ac
font_01_sfnt_off0000eaf2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEAF2 10684 bytes
SHA-256: 3b623a10f814159e7344e3059980879da50ae2a64f9b55309a29ba36cb9236ef
font_02_sfnt_off0001038f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1038F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1