Malicious PDF — malware analysis report

Static analysis result for SHA-256 873aebb023a7d389…

MALICIOUS

PDF

84.0 KB Created: 2021-07-29 19:07:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 176f935898811ccb952a1a49c73d7b90 SHA-1: b8e5739fd3ec5e3185f8b7babcef1ab18c082c24 SHA-256: 873aebb023a7d389e8ba6ddd836e0224b828265b72d7c7df62e010a652230c09
156 Risk Score

Malware Insights

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

The PDF was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it contains a link farm pointing to compromised WordPress upload storage, suggesting a phishing or malware distribution attempt. The document body is heavily obfuscated and unreadable, providing no further context on the specific lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9944

Heuristics 6

  • 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.
  • 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://dmn.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160a7951f8f9ee---80104906417.pdf In PDF document text
    • http://xiaohecollege.com/d/files/bapelujusagim.pdfIn PDF document text
    • https://sellos-mecanicos.com/wp-content/plugins/super-forms/uploads/php/files/e74b619b79898288d256a09173874453/28794928625.pdfIn PDF document text
    • http://amadpich.com/userfiles/file/29072958361.pdfIn PDF document text
    • http://www.scmphotography.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160a92996e0c26---moxukubeguzusoferepopaxu.pdfIn PDF document text
    • http://smclassof57.org/clients/34860/File/supup.pdfIn PDF document text
    • http://www.kickcommerce.com/userfiles/file/jakutebofizuzipidunufag.pdfIn PDF document text
    • http://smithmurdock.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606fb37041671---53980173189.pdfIn PDF document text
    • https://www.frankreich-ferien.ch/wp-content/plugins/formcraft/file-upload/server/content/files/16077918215707---jipabimabor.pdfIn PDF document text
    • http://audiencefertilization.com/fckeditor/editor/filemanager/connectors/php/userfiles/file/92127279536.pdfIn PDF document text
    • https://aimhc.com/userfiles/file/sifuvifinutomi.pdfIn PDF document text
    • http://nnk.gr/wp-content/plugins/formcraft/file-upload/server/content/files/16080e9c25f105---11927905248.pdfIn PDF document text
    • http://www.ponderosafestival.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607b122987db1---wubusivugolenigafaxoru.pdfIn PDF document text
    • https://techson-cctv.com/upload/file/fumijinojuxugexoveteliwef.pdfIn PDF document text
    • https://www.grecosalesinternational.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609a07e0e03de---71477860225.pdfIn PDF document text
    • http://www.danvillern.com/wp-content/plugins/super-forms/uploads/php/files/a15m0h8cdnb8qa5qgd14vhop72/pejisigodedepar.pdfIn PDF document text
    • http://learnersdigest.org/userfiles/file/bazizirebesosala.pdfIn PDF document text
    • http://khodahoanglang.com/admin/webroot/upload/image/files/39892020872.pdfIn PDF document text
    • https://www.arphplumbing.co.uk/wp-content/plugins/super-forms/uploads/php/files/4k4f9ujqihqijn2bbih4fe1j02/53516597418.pdfIn PDF document text
    • https://www.cfo-search.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b66ac6a2197---gonejugogepanumarup.pdfIn PDF document text
    • http://dothi.info/images/files/56466443876.pdfIn PDF document text
    • https://www.allterra.group/wp-content/plugins/super-forms/uploads/php/files/554e49f480397737150616d0ea1a9891/pajujinotazotibaweranovo.pdfIn PDF document text
    • http://zadonskiy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160a6522a90087---xukelulonupisunu.pdfIn PDF document text
    • https://www.hamburgeriaagricola.com/wp-content/plugins/super-forms/uploads/php/files/snsja8oi4oqccaeqvvenrg32ub/jiwowetafejonujeritodi.pdfIn PDF document text
    • https://www.dazzlingdecor.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1609801522c12b---siseluzafexowuzelufe.pdfIn PDF document text
    • https://aymsoft.us/aym_image/files/subobikofanewujegudime.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/ngfLrbzwjls/uplcv?utm_term=soluciones+hipertonicas+isotonicas+y+mezclasPDF 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_off0000df70.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDF70 10988 bytes
SHA-256: e71f78bdfb64135014b99609d16cb6530a585b0cfecbcfe837e4f74ce5571bbb
font_01_sfnt_off0000f8cb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF8CB 18424 bytes
SHA-256: c35709b3365461df884333ce8c932dc0cf4fde3d133468a1c97e2aa09e0f330e
font_02_sfnt_off00012786.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12786 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1