Malicious PDF — malware analysis report

Static analysis result for SHA-256 b68a26bd8463a3f4…

MALICIOUS

PDF

84.7 KB Created: 2021-07-17 20:52:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-13
MD5: be6e3cee50be25b2abef4820fcaf8541 SHA-1: 95accf62a19dd4bded0e7a3e88d1a2e190ae4808 SHA-256: b68a26bd8463a3f40fdb44c35315fae99a7ef95757683bff93d4917f5c0deef2
96 Risk Score

Malware Insights

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

The PDF contains a large number of links pointing to various domains, many of which appear to be disposable or compromised, as indicated by the 'PDF_SEO_DISPOSABLE_LINK_FARM' and 'PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM' heuristics. The ML classifier also strongly flagged this PDF as malicious. The primary function appears to be directing users to external resources, potentially for SEO spam or to host further malicious content, rather than containing an active exploit within the PDF itself.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

Heuristics 5

  • 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 https://maydongy.com/wp-content/plugins/super-forms/uploads/php/files/d77lja7lr2pechn66fqqp3huig/tazedeb.pdf In PDF document text
    • http://sun-tes.ru/files/file/95055567764.pdfIn PDF document text
    • http://gulfcoolcontracting.com/uploads/userfiles/file/file/sekinu.pdfIn PDF document text
    • http://beergolfers.com/blog/images/file/latuxizidujigusolepeguk.pdfIn PDF document text
    • http://pulsarvn.com/media/ftp/file/mipudutiwinesadi.pdfIn PDF document text
    • http://nuyewpilot.academy/wp-content/plugins/super-forms/uploads/php/files/de8b920666b40e6af02ec75d3267f05f/53033025082.pdfIn PDF document text
    • http://e-sportis.com/images/upload/3581021562.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a498b33eb39---wepuxobidopigamusixag.pdfIn PDF document text
    • http://hjtech.org/admin/upfile/file/21350991757.pdfIn PDF document text
    • http://smartraoptics.com/fck_filemanager_upload/file/75063985567.pdfIn PDF document text
    • http://cgt-fo-csc.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160b58f5e48f2d---majusuf.pdfIn PDF document text
    • http://m2m2design.com/userfiles/59519972535.pdfIn PDF document text
    • http://lempreintedubois.fr/userfiles/lempreintedubois.fr/file/pawijanezinuvutafu.pdfIn PDF document text
    • https://www.marthatrotts.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160a190c694a0c---62774836065.pdfIn PDF document text
    • http://www.wallisandemmanuel.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608718da485ad---99255693286.pdfIn PDF document text
    • https://ijmscr.com/ckfinder/userfiles/files/meguposogedutawezikos.pdfIn PDF document text
    • http://www.veronicaneal.com/wp-content/plugins/formcraft/file-upload/server/content/files/1/160760d5ee0bef---30762814371.pdfIn PDF document text
    • http://www.tenniscanberra.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1607d98506ac9f---2248116367.pdfIn PDF document text
    • https://refour.dk/wp-content/plugins/super-forms/uploads/php/files/75d6f129ffe6937e132c4ffaf7801dd4/6049381252.pdfIn PDF document text
    • https://www.auditek.fr/wp-content/plugins/formcraft/file-upload/server/content/files/16072b808694c0---92967772046.pdfIn PDF document text
    • https://www.olympusnorge.no/wp-content/plugins/super-forms/uploads/php/files/ktsd0lu7j8daen7iqllm4s3h3c/40446640697.pdfIn PDF document text
    • http://caacoding.net/wp-content/plugins/formcraft/file-upload/server/content/files/1609cf497638b3---96015127254.pdfIn PDF document text
    • https://amagi.la/wp-content/plugins/formcraft/file-upload/server/content/files/160cef58bc04df---53821749166.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/cv9VXjIrmdE/uplcv?utm_term=32+ounces+equals+how+many+pintsPDF 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_off0000e37e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE37E 18260 bytes
SHA-256: 260fe6da5cd5bc2af3a0ae169a3cf30d1d5e0280c1796104b4a39cf0cee3ced0
font_01_sfnt_off00011359.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11359 11180 bytes
SHA-256: 297252aac46bf5520586f48de269229ad61dbf59f28a746419f0a9ac624e3ac8
font_02_sfnt_off00012d7b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12D7B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1