Malicious PDF — malware analysis report

Static analysis result for SHA-256 8f5272c3f9a64900…

MALICIOUS

PDF

82.5 KB Created: 2021-09-10 06:17:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 56cd32bd5d71883402c1eeac4f0a6ee7 SHA-1: ea839113bc3b4d3ec984b676558c4721f802b744 SHA-256: 8f5272c3f9a649005db69aa667cf04eb13571e35f7389b2ccdf2fcd509d55c3c
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, with numerous URLs pointing to various domains, some of which are hosted on compromised CMS upload storage or disposable hosting. The embedded URLs are designed to lure users to external sites, likely for credential harvesting or further malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

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://booklandbooks.com/userfiles/file/56865730739.pdf In PDF document text
    • http://molenat-energies.fr/molenat.com/images/editor/file/73666943459.pdfIn PDF document text
    • https://mysilo.com/upload/ckfinder/files/manupetuzixo.pdfIn PDF document text
    • http://cargo3030.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16132da6b0fde7---76659900830.pdfIn PDF document text
    • http://holmeslawfirm-iowa.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/gisunavosubudoxokodi.pdfIn PDF document text
    • http://vivatbacchus.hu/files/file/48273687841.pdfIn PDF document text
    • https://livewireeventz.com/userfiles/file/wenibewibotog.pdfIn PDF document text
    • http://acsalma.hu/userfiles/files/1583217657.pdfIn PDF document text
    • http://vizit-k.net/uploads/editor/files/nilizujujesowof.pdfIn PDF document text
    • https://mami-m.com/Uploads/userfiles/files/58493448233.pdfIn PDF document text
    • http://brucemayrockinstitute.com/assets/ckfinder/core/connector/php/uploads/files/savuf.pdfIn PDF document text
    • http://022-web.cn/uploadfile/file/20210906065744526.pdfIn PDF document text
    • http://busangh.com/attfile/fckimg/file///20210901154523_888691658.pdfIn PDF document text
    • http://studiomalpocher.it/userfiles/files/pulakodatolinal.pdfIn PDF document text
    • http://air-ned.com/uploads/files/bakataralakipepe.pdfIn PDF document text
    • https://dungcuruamui.com/wp-content/plugins/super-forms/uploads/php/files/pta9nrsajgucq1lbjr7ssa3ru8/megetukafafe.pdfIn PDF document text
    • https://yourdentist.ro/app/webroot/files/userfiles/files/pedigodumuvi.pdfIn PDF document text
    • https://naseeha.org/wp-content/plugins/super-forms/uploads/php/files/977f70227ce4073e4c6e7b54f182d572/rojawixaforuret.pdfIn PDF document text
    • https://sklep-pinokio.pl/web/uploads/files/banatisumufagozekobafufo.pdfIn PDF document text
    • http://holidayinntorino.com/userfiles/files/63528290866.pdfIn PDF document text
    • https://edu-mate.kr/_UploadFile/Images/file/posanekikidorejizerubiz.pdfIn PDF document text
    • https://loyallcanada.com/editor_files/file/mejirowudosa.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/DOqCt-cVA4I/uplcv?utm_term=stick+war+legacy+2+free+playPDF 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_off0000d718.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD718 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ef2f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF2F 10748 bytes
SHA-256: 6da4cb702a92792b4d08cfd3452022522a10f1fddd97a74307436d878d4a5ffc
font_02_sfnt_off00010834.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10834 19600 bytes
SHA-256: 6b8f9a90643caac176db8cfb37d935e0ba4362581a968a4e054e5480feeba8cf