Malicious PDF — malware analysis report

Static analysis result for SHA-256 657f57c9b3c58436…

MALICIOUS

PDF

69.8 KB Created: 2021-09-06 04:09:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 94440f85374ac0a8c5ad35085bf08d66 SHA-1: 47f2ab522ab5602c92eaf6d98eb16a253d2c4412 SHA-256: 657f57c9b3c5843612009a78d496c1d4e2b93de7e323984a87000e6ecaca80c7
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and a significant number of external links, many pointing to compromised WordPress sites or disposable hosting, indicating a link farm designed for malicious redirection. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware delivery via these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9982

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://www.alexgis.com/siteuploads/editorimg/file/36253687167.pdf In PDF document text
    • https://www.wikiwebagency.it/wp-content/plugins/super-forms/uploads/php/files/dfd6c12abc0e4318a733fac02f59bad3/jobinu.pdfIn PDF document text
    • http://xn--90aoaidn.xn--p1ai/ckfinder/userfiles/files/ludasuwixep.pdfIn PDF document text
    • http://vtaky.sk/media/file/91796908984.pdfIn PDF document text
    • http://easternsheep.by/app/upload/file/sewawojubuxuk.pdfIn PDF document text
    • http://titibbs.xyz/js/ckfinder/userfiles/files/33754371793.pdfIn PDF document text
    • https://www.llgnjinc.com/wp-content/plugins/super-forms/uploads/php/files/c47e3da33ee1b8ae307b5d2839bee0e0/89236777529.pdfIn PDF document text
    • https://bbgpiti.com/userfiles/files/49047336588.pdfIn PDF document text
    • http://brodart01.com/wp-content/plugins/super-forms/uploads/php/files/i86pmnj1cln7tv7dhgeqdmq6i1/nivufaxafi.pdfIn PDF document text
    • https://ebal.ro/app/webroot/files/userfiles/files/92046070410.pdfIn PDF document text
    • https://unicornccc.com/ckfinder/userfiles/files/vibudasib.pdfIn PDF document text
    • http://www.zulfugar.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16071b2da8d723---wafalodovovawifixojuzo.pdfIn PDF document text
    • https://www.vigo.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160d7317addb5c---6445067586.pdfIn PDF document text
    • https://lakecountyoralsurgery.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c091ab8c088---25147524960.pdfIn PDF document text
    • http://goddesshair.net/upload/users/files/68499444194.pdfIn PDF document text
    • http://myslizdrave.com/soubory/zonasuvurepo.pdfIn PDF document text
    • http://www.risingstars.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/160d428400d3eb---jozatiwozojuji.pdfIn PDF document text
    • https://asiatravel.kg/wp-content/plugins/super-forms/uploads/php/files/9644ffe881602ab0fe79ec9a38edd7c2/kusamuvikulawamatufa.pdfIn PDF document text
    • http://urbanelect.com/userfiles/file/55258038453.pdfIn PDF document text
    • http://taiwangallant.com/uploads/files/202108201745409716.pdfIn PDF document text
    • http://www.primalegal.eu/wp-content/plugins/super-forms/uploads/php/files/bin0cnntiv6i4u150a5r8pj4e1/vurudas.pdfIn PDF document text
    • https://inijariku.com/ckfinder/userfiles/files/waruvimewasegajegulira.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/6naE_Nh8_CY/uplcv?utm_term=thule+roof+rack+instructions+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_off0000b438.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB438 14948 bytes
SHA-256: 4c5d21833fd2a88ad82f3e603c9526290279bfc2507ff469485261880b6d9d06
font_01_sfnt_off0000d912.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD912 10756 bytes
SHA-256: a8cfe25e9ce1f9bde9377fd7e7f112447aa9f314578e9a7b7df5905049c44c6e
font_02_sfnt_off0000f1b1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF1B1 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1