Malicious PDF — malware analysis report

Static analysis result for SHA-256 40fbaaa961650534…

MALICIOUS

PDF

119.1 KB Created: 2021-06-28 12:09:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 50cbe4e14c93939df1cfcf73848c33f7 SHA-1: ea1478a142e6fa0f5f835f49ac2e70781ced44f4 SHA-256: 40fbaaa961650534bee486f1214175f37c5fe6ba2787302c777ee33110fb33bb
156 Risk Score

Malware Insights

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

The PDF contains a link farm pointing to multiple compromised WordPress sites, likely intended to lure users to malicious content. The ClamAV detection and ML classifier strongly indicate malicious intent, classifying it as a phishing trojan. No scripts were extracted, but the structure suggests it's designed to exploit users via indirect links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9858

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 https://tfnd.org/wp-content/plugins/super-forms/uploads/php/files/d31808a36f10bdcde2d4a1e52f1aaeb5/94308362702.pdf In PDF document text
    • https://ceilford.org/wp-content/plugins/super-forms/uploads/php/files/6586412113d1479cc21049177d2f9011/77633384407.pdfIn PDF document text
    • https://dewalt-naradi.cz/media/upload/editor/file/tesapaxevubar.pdfIn PDF document text
    • http://ar-intl.net/wp-content/plugins/super-forms/uploads/php/files/99rscle02bd2005jsrh4viisu3/80341945564.pdfIn PDF document text
    • http://vdtonline.vn/static/uploads/editor/files/95110687136.pdfIn PDF document text
    • http://saxonsaxtonfamilyreunion.com/clients/f/f6/f6d0431f970e0833b0867c311dafb132/File/90898961984.pdfIn PDF document text
    • https://www.tangelo.no/wp-content/plugins/formcraft/file-upload/server/content/files/160794afe2162d---28664972447.pdfIn PDF document text
    • http://haileylusk.com/clients/e/e6/e6412a3df854040bfb282c4f37eddf02/File/22917919492.pdfIn PDF document text
    • http://normandyclassof79stl.com/clients/e/e1/e16d7b8530e96d8d426d6b963c92b0b5/File/dabajedir.pdfIn PDF document text
    • http://apvn.info/userfiles/file/94806821795.pdfIn PDF document text
    • http://mirembeestate.co.ug/wp-content/plugins/formcraft/file-upload/server/content/files/1607843dbbe3ad---jovezuwusupukuzejuf.pdfIn PDF document text
    • http://nek.ua/wp-content/plugins/formcraft/file-upload/server/content/files/160c7ae5cd06ac---towiwoxiwazilerofas.pdfIn PDF document text
    • http://wingprocess.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/gexukifo.pdfIn PDF document text
    • https://frasertechno.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c87c149d154---rumajubibewe.pdfIn PDF document text
    • https://www.generalutilities.com/wp-content/plugins/formcraft/file-upload/server/content/files/16099c15bcfd67---19344261381.pdfIn PDF document text
    • http://jockmurray.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609e07e0c7a50---zedurupuvetaxusumuram.pdfIn PDF document text
    • http://www.tif.cn/wp-content/plugins/super-forms/uploads/php/files/29vviscoamabc8hubuq3lnjjls/67136208882.pdfIn PDF document text
    • http://xn----8sbpvg0afdbe.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/8nqp8ukf54kroh4v3msd0i7dg7/dusexelibujo.pdfIn PDF document text
    • http://victorylimo1.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608b94e3b13eb---79145758805.pdfIn PDF document text
    • https://xn----7sbbjg7ctfs.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/8346b7824728679f102834e92e59a6e4/jizajigu.pdfIn PDF document text
    • https://iword.de/userfiles/file/labimaxobisekitedubun.pdfIn PDF document text
    • https://estigotours.com/wp-content/plugins/super-forms/uploads/php/files/88c3495b3f069804217bdc2628a8638c/78969844546.pdfIn PDF document text
    • http://hemeringen.de/ckeditor_ablage/userfiles/files/lejudemufidu.pdfIn PDF document text
    • https://stcatherine.ac.ug/wp-content/plugins/formcraft/file-upload/server/content/files/1608673e6aacb8---lezuzewavab.pdfIn PDF document text
    • http://giftboxvietthuy.com/upload/ck/files/gumitokefenefonejoke.pdfIn PDF document text
    • https://www.mercedesbenzofaustinservice.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a1fe8c4d3a0---nozanugorakijojasovaluke.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/PmAiG5ZyT-k/uplcv?utm_term=operant+conditioning+theory+of+learningPDF 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_off00016ef6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x16EF6 17968 bytes
SHA-256: 74761e49f1fafe0b3b23ece6d51d8231a57a09e28accf63b4985a05b994dffda
font_01_sfnt_off00019e0e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x19E0E 10872 bytes
SHA-256: 2b3aa98723ae731848f422f9d65f25fbe13102bdeddf0833147d7e878dda57a7
font_02_sfnt_off0001b6ee.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1B6EE 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1