Malicious PDF — malware analysis report

Static analysis result for SHA-256 99c9ff616253a2f5…

MALICIOUS

PDF

86.1 KB Created: 2021-07-30 06:59:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-02
MD5: 8fa96d5fc676ac56c53c3a6df48416d5 SHA-1: 60b6d7c89222aa5fd85f0b2568d3a5723ad865c2 SHA-256: 99c9ff616253a2f5c4e32198cf10e854d09c386df79789e20ad66a9a0217435b
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

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 https://www.dyna-tech.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160d7d80e25c0d---39596519335.pdf In PDF document text
    • http://israel-aliya.com/wp-content/plugins/super-forms/uploads/php/files/fae8490165092d8453c9f73441d766d5/gudopobebij.pdfIn PDF document text
    • http://www.dereformasenalicante.com/archivos/files/gizifi.pdfIn PDF document text
    • https://tranduongauto.com/app/webroot/files/images/pages/files/51012206085.pdfIn PDF document text
    • http://www.nuricomuvakfi.org/wp-content/plugins/super-forms/uploads/php/files/it0p8ek1j2m21hbtkiqclt30i3/15704170546.pdfIn PDF document text
    • https://adbetelparaguay.com/wp-content/plugins/super-forms/uploads/php/files/8131c1ac194d53fd9fd16cde98dbc424/wefetimomuvinilepaxeb.pdfIn PDF document text
    • https://greshamgilessalon.com/wp-content/plugins/super-forms/uploads/php/files/b70efbcdae25d95956e02d2511f1ffd7/81958469398.pdfIn PDF document text
    • http://www.northeastmarquees.com/wp-content/plugins/super-forms/uploads/php/files/900c154618b0a79142931f7607b1dd4f/wopamomufekafe.pdfIn PDF document text
    • https://alexandrapanayotou.com/web/images/static/file/92644303569.pdfIn PDF document text
    • http://manavpublicschool.org/manav/userfiles/file/8967762829.pdfIn PDF document text
    • http://cfacgroup.com/uploads/FCK_files/file/79900162638.pdfIn PDF document text
    • http://becro-plast.hr/wp-content/plugins/formcraft/file-upload/server/content/files/160f3aac52acf5---41723818340.pdfIn PDF document text
    • https://www.edutechusa.com/wp-content/plugins/formcraft/file-upload/server/content/files/160cd458ba9b15---faboxuju.pdfIn PDF document text
    • https://kfz-gutachter-oliver-schiller.de/wp-content/plugins/formcraft/file-upload/server/content/files/16090998bb1674---punaludigana.pdfIn PDF document text
    • http://queuemanagementsystems.com/wp-content/plugins/formcraft/file-upload/server/content/files/16079d8fff3a1a---futaxi.pdfIn PDF document text
    • http://vtracauto.com/wp-content/plugins/formcraft/file-upload/server/content/files/16089d5272b3a2---laxapolifiretiromukigat.pdfIn PDF document text
    • http://nirmalamathachurch.org/cms_uploads/image/file/faxonomeg.pdfIn PDF document text
    • https://webmodeli.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d87ecfe2c9d---31888073157.pdfIn PDF document text
    • http://streetnn.ru/data/upload/ck/files/dulubekobepowigolam.pdfIn PDF document text
    • http://allasclub.com/campannas/file/57287144934.pdfIn PDF document text
    • http://johndanton.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/nakatijiri.pdfIn PDF document text
    • http://wsp.pl/userfiles/file/97338060032.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/A3Ryygt5BCM/uplcv?utm_term=developmental+biology+scott+gilbert+11th+edition+pdfPDF 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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d531.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD531 17048 bytes
SHA-256: 99c35f0313d82c6ca5fcc97fb04ac7cafab5ef1fd9e46c986590cd32a6ffed0a
font_01_sfnt_off0001018b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1018B 16084 bytes
SHA-256: a79c9caf7d9fe7d7e6557dd08284a48a0650ee9668136fadcfdab94fba17ddb2
font_02_sfnt_off000116bf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x116BF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_03_sfnt_off00012ed6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12ED6 11440 bytes
SHA-256: a85589dbe6f21825a39650ae5c07f4556b968fa14e26624d6222fd4b2d80f2f3