Malicious PDF — malware analysis report

Static analysis result for SHA-256 3e1bf4a216116be5…

MALICIOUS

PDF

83.2 KB Created: 2021-09-05 06:55:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: bb2165491447e36520ee4621ee7d69a1 SHA-1: dc343436e19a50f957485d6ace3bcda415e80c27 SHA-256: 3e1bf4a216116be5bfe8238306f66656666cb96ab9bf45f231605b13fda0978b
156 Risk Score

Malware Insights

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

The PDF contains a link farm with numerous URLs, several of which point to compromised CMS upload directories. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. No scripts were extracted, and the document body was unreadable, so the primary indicators are the embedded URLs and heuristic firings.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://majstrissmt.eu/www-data/file/53595290610.pdf In PDF document text
    • https://anpheatingandac.com/nbloom/fckuploads/file/zebidoxotelojijegelepu.pdfIn PDF document text
    • https://balance-global.com/wp-content/plugins/super-forms/uploads/php/files/f98a8mug1aagfm5v7jt5n5c4ag/kigubamoseniti.pdfIn PDF document text
    • https://www.sharpeningfactory.com/wp-content/plugins/formcraft/file-upload/server/content/files/160837c2ccac11---2364451893.pdfIn PDF document text
    • http://vladjurnalist.ru/archive/file/6834559144.pdfIn PDF document text
    • http://horlickhigh61.com/clients/a/ab/ab3fb267cc30d45b98f460a20cee0b8d/File/voxuxaziwunanet.pdfIn PDF document text
    • http://3duct.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c30d959c01c---sukubudivefos.pdfIn PDF document text
    • https://bakotech.at/uploads/ckeditor/files/68602246054.pdfIn PDF document text
    • http://minhledtran.com/luutru/files/65735883438.pdfIn PDF document text
    • https://www.techsrollout.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a57fd2a8817---gixizotapepojepalojujubex.pdfIn PDF document text
    • http://www.suffaheducation.com/wp-content/plugins/formcraft/file-upload/server/content/files/16073aac125f0d---zabadaxedake.pdfIn PDF document text
    • https://intelean.com/wp-content/plugins/formcraft/file-upload/server/content/files/16079981f2c708---duzikubisudageworogawu.pdfIn PDF document text
    • https://sygimportaciones.com/wp-content/plugins/super-forms/uploads/php/files/ing1bh15l48l2u7gb8su3fc1ug/fufexipekaturalipapaxezop.pdfIn PDF document text
    • https://xrtradingfeedback.com/cmsimages/file/2173635277.pdfIn PDF document text
    • http://modnyi-buket.ru/uploads/files/sefuruwumebuxelefuwom.pdfIn PDF document text
    • http://zlzljc.com/uploadfile/file///2021080401590589.pdfIn PDF document text
    • http://stroisvias.ru/userfiles/file/26888727044.pdfIn PDF document text
    • http://stigstudiotecnico.it/userfiles/files/28964768268.pdfIn PDF document text
    • http://ecbpolska.pl/wp-content/plugins/super-forms/uploads/php/files/5b85ebea59d1a302db4f95706cbcec4c/fotozipuvaxexudafojas.pdfIn PDF document text
    • http://stlnsk.ru/uploads/file/73793329216.pdfIn PDF document text
    • https://janeunchained.com/wp-content/plugins/super-forms/uploads/php/files/6g0slo374e2nlp1tsdkkfqah8s/19747416389.pdfIn PDF document text
    • https://hopefor.today/wp-content/plugins/super-forms/uploads/php/files/d590f54a308005a9c5315acd9f99e24d/8160996858.pdfIn PDF document text
    • https://www.escon.it/wp-content/plugins/super-forms/uploads/php/files/69fd4d0d6a20a4ce71bd96030969e394/26206923637.pdfIn PDF document text
    • http://xn--90ad5ackt1d.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/ec90cb7c2c67d0dc85d19b3a21228d3a/47626968199.pdfIn PDF document text
    • http://clubcrudupsonoma.com/clients/1/14/14cf715f5cd05ddba197ceaa5938d7d5/File/36138591009.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/zMnd8XtcwSM/uplcv?utm_term=briggs+stratton+ohv+engine+repair+manualPDF 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_off0000e222.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE222 16716 bytes
SHA-256: 47100fa6f85372e2f062f0081ae9231bb74701fae95dc411b9ea7e960498c1e3
font_01_sfnt_off00010d71.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10D71 10920 bytes
SHA-256: 5c29d19d2d1acf566d93c8398a84a0e4357e6baae1c98328f40ad0f014172d37
font_02_sfnt_off00012693.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12693 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1