Malicious PDF — malware analysis report

Static analysis result for SHA-256 a16c27e75d66776a…

MALICIOUS

PDF

72.2 KB Created: 2021-09-30 21:17:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: ef8cc79457722a5f258a1ede7309dea2 SHA-1: ac2975983d7ffdfaae33537422530e29cda31f38 SHA-256: a16c27e75d66776ab6b0f9d705e5ed77717ee836fc645b7c9f7a2c372058c599
156 Risk Score

Malware Insights

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

The PDF file was flagged by multiple heuristics as malicious, including a critical ClamAV detection and an ML classifier. It contains numerous embedded URLs, many of which point to compromised CMS upload storage or are part of a link farm on disposable hosting, indicating a phishing or malware distribution attempt. The presence of these links suggests the document's primary purpose is to redirect users to potentially harmful external sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9982

Heuristics 6

  • 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.
  • 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://wakabaeducation.com/userfiles/file/7985871593.pdf In PDF document text
    • https://banerjeetourspecial.in/ckfinder/userfiles/files/80487419669.pdfIn PDF document text
    • http://ingore.cn/upload/files/3137607119.pdfIn PDF document text
    • http://rsst77.ru/upload/files/41637935738.pdfIn PDF document text
    • https://ntct-dz.com/ckfinder/userfiles/files/15253457374.pdfIn PDF document text
    • http://northmarking.com/userfiles/files/jivix.pdfIn PDF document text
    • https://www.goldenplanet.dk/wp-content/plugins/formcraft/file-upload/server/content/files/16146c47f2d2de---86639134299.pdfIn PDF document text
    • http://deccanquest.com/konadnew/userfiles/file/83125813480.pdfIn PDF document text
    • http://angarakshaksecurity.com/userfiles/file/wivalo.pdfIn PDF document text
    • http://signexpowholesale.com/project-new/christianbook/upload_images/file/panajem.pdfIn PDF document text
    • https://quangcaowebsite.xemlaco.com/uploads/files/9073692758.pdfIn PDF document text
    • http://aristosaigonhotel.vn/uploads/files/mixewaguzid.pdfIn PDF document text
    • http://eptesteplelek.com/uploads/file/45798147037.pdfIn PDF document text
    • https://pacpartner.net/images_client/imagesfile/24489400545.pdfIn PDF document text
    • https://kalatranslation.co.uk/wp-content/plugins/super-forms/uploads/php/files/e56ptkchofmrp5uok48vvmkuks/jemat.pdfIn PDF document text
    • http://zeci.nl/im/image/debapareti.pdfIn PDF document text
    • https://bizdrive.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1/161535b63b7579---refurukix.pdfIn PDF document text
    • http://eis-pieschel.de/UserFiles/File/xegumodasulume.pdfIn PDF document text
    • http://www.sindafaz.com.br/admin/editor/ckfinder/userfiles/files/fuxedu.pdfIn PDF document text
    • http://thuduchouse.vn/pics/file/tududimefijadulukid.pdfIn PDF document text
    • http://studiomarazzi.eu/userfiles/files/54589056830.pdfIn PDF document text
    • http://lirealestatelitigator.com/wp-content/plugins/super-forms/uploads/php/files/492b6f064ddee268ad9e6742bad2ea51/66296789242.pdfIn PDF document text
    • http://eco-building.cz/UserFiles/File/rigomewipelaketidugirekoj.pdfIn PDF document text
    • http://hataylezzeti.com/resimler/files/kawuvowutefaterutoja.pdfIn PDF document text
    • https://www.albriug.com/static/editor/ckeditor/ckfinder/upfile/files/84249981665.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/zMnd8XtcwSM/uplcv?utm_term=kickin+it+seafordPDF 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_off0000b740.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB740 10504 bytes
SHA-256: 9e92705d85f2d21ba7a5a6554dc637bbdd0aa7e0f84eb1178dc2a7eee04a347a
font_01_sfnt_off0000cf51.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCF51 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000e763.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE763 17352 bytes
SHA-256: 82ff3d89b54ea009e6e81f25ba7dd62789a29ab71a035f7769dc8d0ca4cd8206