Malicious PDF — malware analysis report

Static analysis result for SHA-256 1cb330bff52863ee…

MALICIOUS

PDF

84.3 KB Created: 2021-09-02 03:00:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 9590c23be718f883f18588723614c200 SHA-1: 3c2b1487489213c5886a14223cef4ea33c91ca63 SHA-256: 1cb330bff52863ee06f04c416263b2c06dacdd50d385ce39e01bb4b6b15d395a
156 Risk Score

Malware Insights

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

The PDF was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, with numerous URLs pointing to compromised WordPress sites, likely serving as a distribution point for malicious content. The document body is heavily obfuscated and unreadable, providing no direct user-facing lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9983

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://www.onekaddy.com/wp-content/plugins/formcraft/file-upload/server/content/files/161048597b6262---dimabozowidodar.pdf In PDF document text
    • http://evabody.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16109e8212538a---13511048524.pdfIn PDF document text
    • https://www.davidcosz.de/wp-content/plugins/super-forms/uploads/php/files/e5fcjn2su41nh07qll1us499pu/nolezedulenak.pdfIn PDF document text
    • http://www.kmclogistics.com/wp-content/plugins/super-forms/uploads/php/files/d6e10475f8913a34647f31f06b463b54/55353571892.pdfIn PDF document text
    • https://www.hed-endo.hr/wp-content/plugins/formcraft/file-upload/server/content/files/160f690cdafd46---6927523003.pdfIn PDF document text
    • https://www.kalirich.com/wp-content/plugins/super-forms/uploads/php/files/k02f60ot3gngehem9h5iererr5/28687422816.pdfIn PDF document text
    • http://lammermoor.net/imagenes/file/94661595094.pdfIn PDF document text
    • http://mynigaoe.com/upload/file/20210703114327.pdfIn PDF document text
    • http://www.cuerpomenteyespiritu.es/wp-content/plugins/formcraft/file-upload/server/content/files/1612d3d65c6dc4---9783674485.pdfIn PDF document text
    • https://www.areatransfers.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607f93534c26f---rarudelukakor.pdfIn PDF document text
    • https://cengilli.com/icerik_images/file/juvejenalabifade.pdfIn PDF document text
    • https://dsodrecital.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bbc1d1c73b6---39827062842.pdfIn PDF document text
    • http://freehajjandumrah.com/admin/admin/uploadfiles/file/nafifenekekekomuj.pdfIn PDF document text
    • https://orrizon.ru/images/file/61866972273.pdfIn PDF document text
    • http://www.rify.us/cms-uploads/files/livifaredinaso.pdfIn PDF document text
    • http://travellightnepal.com/userfiles/file/babizoxelowewuj.pdfIn PDF document text
    • http://plenaadoracao.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160766365de963---65823990048.pdfIn PDF document text
    • https://xn----9sbccjdbca7cyaieg1a3j.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/ebd758cacdcefa1822461c600cf8c0b9/38076152256.pdfIn PDF document text
    • https://zlatartopalovic.rs//files/xuzilujevuwixe.pdfIn PDF document text
    • http://clearlakesd.org/wp-content/plugins/formcraft/file-upload/server/content/files/16096aada2af64---xebotafurizokunobe.pdfIn PDF document text
    • https://kolodezrus.ru/wp-content/plugins/super-forms/uploads/php/files/f1c7d4a48f02cf030a4226bd1e5f76a5/zumirunas.pdfIn PDF document text
    • http://absolutelyneon.com/userfiles/file/virekezozopidip.pdfIn PDF document text
    • https://www.verpoort-bouw.be/wp-content/plugins/formcraft/file-upload/server/content/files/160904de28e7d8---62101088931.pdfIn PDF document text
    • http://cohn-vossen.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a756ecbfe29---3962316347.pdfIn PDF document text
    • https://www.napariverinn.com/wp-content/plugins/super-forms/uploads/php/files/19c2c901f83f9c0b46c078e3780965e4/11027984290.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/GLLx1DTH0VQ/uplcv?utm_term=one+two+three+letter+wordsPDF 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_off0000e553.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE553 17800 bytes
SHA-256: e3a7ef8b2dc97f61ead04ce5fd2c99809eedadc22426fe6f1d2e260894cd308a
font_01_sfnt_off000113b3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x113B3 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012bca.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12BCA 10200 bytes
SHA-256: 3f6d8c465fa369f9d486773f601be2734ec48ab20467a8b87d6ca71880b8b796