Malicious PDF — malware analysis report

Static analysis result for SHA-256 3878eb22b90751b8…

MALICIOUS

PDF

160.1 KB Created: 2021-08-08 18:34:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 2ce2c02549c852a63584af73b479b82d SHA-1: 4437c8c270590d3eec5493f312b9ef9795530b65 SHA-256: 3878eb22b90751b894810b8662076b716e14b629accfd408482e5b7f3a926e99
156 Risk Score

Malware Insights

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

The PDF contains numerous links, many of which point to compromised WordPress sites utilizing the Formcraft plugin for file uploads. This suggests the PDF is designed to lure users to these compromised sites, potentially for further exploitation or phishing. The ClamAV detection and ML classifier strongly indicate malicious intent, likely related to phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9825

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://lisahyatthealth.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b30b9ae56db---7843471452.pdf In PDF document text
    • https://skillmapmagazine.com/ckfinder/userfiles/files/mojusozugutibulito.pdfIn PDF document text
    • http://jarosi.hu/files/file/sizes.pdfIn PDF document text
    • https://www.formwork.co.uk/wp-content/plugins/super-forms/uploads/php/files/026n7h222kbn38sgqunrd9relt/volaxaw.pdfIn PDF document text
    • https://walterchiropracticclinic.com/home/walter/public_html/ckfinder/userfiles/files/72268779262.pdfIn PDF document text
    • https://dacinsara.ro/fckfiles/file/ratap.pdfIn PDF document text
    • http://caacoding.net/wp-content/plugins/formcraft/file-upload/server/content/files/160fcfbf56ede2---12398139291.pdfIn PDF document text
    • http://www.franklinwebdesign.com/wp-content/plugins/formcraft/file-upload/server/content/files/16084a5355102c---nulewewapozexofef.pdfIn PDF document text
    • http://www.roosprommenschenckelfoundation.nl/ckfinder/files/files/68369562895.pdfIn PDF document text
    • https://pavaniautismschools.com/wp-content/plugins/super-forms/uploads/php/files/rt85cninh7f20fo356k76v7siu/78843605123.pdfIn PDF document text
    • https://levin-dent.ru/wp-content/plugins/super-forms/uploads/php/files/56add76f87f1a5c0e812fd27e0e570d7/zidolagenifikafaro.pdfIn PDF document text
    • http://www.gcsystem.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1610d966c803de---zafexufumezisiz.pdfIn PDF document text
    • http://www.benvenutialmare.com/wp-content/plugins/formcraft/file-upload/server/content/files/160f7e0d71735f---delaperuba.pdfIn PDF document text
    • https://www.sussexweddingservices.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1607784651334c---tunajila.pdfIn PDF document text
    • http://aeskulap24h.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a61f723ed86---pefawiba.pdfIn PDF document text
    • http://premsaktidal.in/userfiles/file/12680904489.pdfIn PDF document text
    • http://erkerlaender.de/wp-content/plugins/formcraft/file-upload/server/content/files/160ab62ea7b025---20142343156.pdfIn PDF document text
    • http://vyveva.eu/UserFiles/File/8792252939.pdfIn PDF document text
    • http://vdadanang.vn/app/webroot/assets/files/luwafujexadawujoxu.pdfIn PDF document text
    • https://bbu.vn/Images_upload/files/dagorutomigaribixubuk.pdfIn PDF document text
    • https://www.accidentinjuryalbuquerque.com/wp-content/plugins/super-forms/uploads/php/files/e8bcfdomem3pqce23hrn50n22o/jekixarurifudinazox.pdfIn PDF document text
    • https://www.passion-rnd.com/upfile/files/2021/07/25/tazexatowa.pdfIn PDF document text
    • http://vanhacollection.com/images/files/gajozanof.pdfIn PDF document text
    • http://geose.ru/userfiles/file/17861865887.pdfIn PDF document text
    • http://thainightjob.com/ckfinder/userfiles/files/85385985892.pdfIn PDF document text
    • http://aivieksteslaivas.lv/userfiles/file/34062865428.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/PmAiG5ZyT-k/uplcv?utm_term=charles+darwin+theory+of+evolution+by+natural+selection+summaryPDF 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_off00020ae7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x20AE7 20084 bytes
SHA-256: db2a07bfbed7b90b1c8900cef5863e6a76008dcdb4ed38f88044ee6999edb4ab
font_01_sfnt_off00023ebb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x23EBB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000256d2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x256D2 11280 bytes
SHA-256: cc7cdb8f4b2fb0b9f7cc96353acd8f437e3b0e86928a7e6e87b507d049c56deb