Malicious PDF — malware analysis report

Static analysis result for SHA-256 737cad769afb289c…

MALICIOUS

PDF

81.3 KB Created: 2021-08-13 07:09:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 1946fe38a54b2115116acc0df8f960cf SHA-1: 0e94e92a12a86242e86933ff861ce122e9a37b0f SHA-256: 737cad769afb289c63cc8daeda0b41dd37196ce5898c90bafc6b1e9ecc6723c8
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ClamAV and an ML classifier, and contains embedded JavaScript. Heuristics indicate it functions as a link farm, pointing to multiple compromised WordPress upload directories, likely to host or distribute malicious content. The presence of JavaScript suggests an attempt to execute code within the PDF viewer, potentially leading to further compromise.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9917

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://osullivanspressurewashing.com/wp-content/plugins/formcraft/file-upload/server/content/files/16098844aa6c82---79139685551.pdf In PDF document text
    • http://ackerviewguesthouse.com/userfiles/file/56176802665.pdfIn PDF document text
    • http://kazenergy.kz/wp-content/plugins/formcraft/file-upload/server/content/files/16084d8f459559---8957461226.pdfIn PDF document text
    • https://lakeshoresmilesdentistry.com/wp-content/plugins/super-forms/uploads/php/files/lao8uin8185j0mvss8dk1ukk80/58588552561.pdfIn PDF document text
    • https://functionalmovement.gr/wp-content/plugins/super-forms/uploads/php/files/caf798075f956e43cf4b5b32e48bc145/25285462787.pdfIn PDF document text
    • http://signaturecruise.com/js/ckfinder/userfiles/files/leruj.pdfIn PDF document text
    • https://lakecountyoralsurgery.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606d8346d6cf3---19196061468.pdfIn PDF document text
    • http://abapaposentados.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160f9347d78c15---60724035731.pdfIn PDF document text
    • http://www.sevenchurchestour.net/seven/wp-content/plugins/formcraft/file-upload/server/content/files/16076539bd30e4---99309136602.pdfIn PDF document text
    • https://electrodomesticaruano.com/images/ckfinder/files/guxowogovono.pdfIn PDF document text
    • https://accesoriosalmayor.com/images/userfiles/file/dozufosatuxemugafon.pdfIn PDF document text
    • https://lightsourceindiana.com/wp-content/plugins/super-forms/uploads/php/files/f6dfb91ddc21e685c29f37a3524c3f2d/7110739947.pdfIn PDF document text
    • https://fivetc.net/uploads/files/pimorari.pdfIn PDF document text
    • https://lynnesnaturaltreats.com.au/wp-content/plugins/super-forms/uploads/php/files/9c0ca031a6d1ae26dcaf3f09a338d4ce/tikimonevubefudimitawojiz.pdfIn PDF document text
    • https://www.saenger-ohg.de/wp-content/plugins/formcraft/file-upload/server/content/files/1610fe697ad253---rimetude.pdfIn PDF document text
    • https://xn--80aaaglcftt5alesfkk7f.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/53c57ffd037d7d0794cc62deced2e1b8/wiwiruvavebovatanu.pdfIn PDF document text
    • http://zadonskiy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160d6a8ff53d40---83870735810.pdfIn PDF document text
    • https://hotelritariccione.it/wp-content/plugins/formcraft/file-upload/server/content/files/16085806016fb6---95874031739.pdfIn PDF document text
    • http://xiangzhuan.tw/upload/files/jisado.pdfIn PDF document text
    • http://secohthailand.com/file_media/file_image/file/29516766454.pdfIn PDF document text
    • https://www.carlosfunes.es/wp-content/plugins/formcraft/file-upload/server/content/files/16084d44a841f0---19843108411.pdfIn PDF document text
    • http://ypperfect.com/ckfinder/userfiles/files/9480920275.pdfIn PDF document text
    • https://stefandes.com/wp-content/plugins/formcraft/file-upload/server/content/files/16093d4cb17b77---42442222663.pdfIn PDF document text
    • https://morethancleaningservices.com/wp-content/plugins/super-forms/uploads/php/files/194871a80b5a2374dfa250ae8c85b9d1/44397624348.pdfIn PDF document text
    • http://antik-cafe-bergen.de/wp-content/plugins/formcraft/file-upload/server/content/files/1610882ec68d7f---sefawerer.pdfIn PDF document text
    • https://www.eoluk.com/wp-content/plugins/super-forms/uploads/php/files/7pjv25o8o99mjk0crf7oud3tqn/jeburimenagesulabupo.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/Om9ozkHLxGw/uplcv?utm_term=1999+chevy+p30+step+van+dimensionsPDF 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_off0000d6bc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD6BC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000eed3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEED3 11232 bytes
SHA-256: 625c2174d29c8895dc0274ae854e21211d0881a01ef0ca816d89f471e8d6cc2d
font_02_sfnt_off0001090e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1090E 17060 bytes
SHA-256: 34e1cac5ff02f4fb92a726f1b1cb72e469521155114f70cd473bf1910b711639