Malicious PDF — malware analysis report

Static analysis result for SHA-256 37afd414b358fa08…

MALICIOUS

PDF

87.5 KB Created: 2021-07-07 00:05:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-25
MD5: b83da4e7a8b0a7c2186faa6f6f5966c7 SHA-1: 86d376cde37f77e09024787f8145ead0fa1b12f8 SHA-256: 37afd414b358fa0827d23d63cf46be73523d89df7520504252eecd1c0a7fc62d
96 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised WordPress sites or disposable hosting, indicating a link farm. The ML classifier strongly flagged this PDF as malicious. While no scripts were extracted, the heuristic firings suggest the document's primary purpose is to redirect users to potentially malicious or SEO-manipulated content hosted on compromised infrastructure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

Heuristics 5

  • 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://behagi.eus/files/galeria/files/81951681358.pdf In PDF document text
    • https://bindazzled.com.au/wp-content/plugins/super-forms/uploads/php/files/b22471dbd82d89a7b0bef9aba0454005/83248703938.pdfIn PDF document text
    • http://phrabat.net/UserFiles/File/nodisidowezevaguru.pdfIn PDF document text
    • http://famcareconnect.org/wp-content/plugins/formcraft/file-upload/server/content/files/160a519522ba4a---duxobizizipejakerugiru.pdfIn PDF document text
    • https://foxtailmag.net/wp-content/plugins/super-forms/uploads/php/files/58ef004e942d67a0db646209ed2ebf40/subepimapomiwajigoro.pdfIn PDF document text
    • http://kaufdeinauto.de/wp-content/plugins/formcraft/file-upload/server/content/files/160b10a0477610---65042681828.pdfIn PDF document text
    • http://vaness-sens.fr/ckfinder/userfiles/files/69825765178.pdfIn PDF document text
    • https://ildiko-szepsegszalon.hu/userfiles/file/fedidefotezenuzawerabo.pdfIn PDF document text
    • http://atlantichomeportugal.com/wp-content/plugins/formcraft/file-upload/server/content/files/16082c4992a7c6---84447048536.pdfIn PDF document text
    • https://freedomtampons.com/wp-content/plugins/super-forms/uploads/php/files/b59c703a9cd88e82b719964330669e0f/75403262020.pdfIn PDF document text
    • https://cor.org.ar/wp-content/plugins/super-forms/uploads/php/files/123flkjomp03d2u8i3dpmud5aa/gajaxujek.pdfIn PDF document text
    • https://wecafephuket.com/wp-content/plugins/super-forms/uploads/php/files/l634h2cfeolfa1stta7md7n6j8/12197760535.pdfIn PDF document text
    • http://betenagro.com/sites/default/files/file/nojuxesosizuripagerot.pdfIn PDF document text
    • https://giolog.biz/images/bulk_images/files/55950847499.pdfIn PDF document text
    • http://cmtsport.com/pliki/makoto.pdfIn PDF document text
    • https://stef-nancy.fr/upload/document/50766235454.pdfIn PDF document text
    • https://acgroupenterprise.com/userfiles/file/lusev.pdfIn PDF document text
    • http://jnnycc.org/userfiles/file/pimurukusejavalukapipexef.pdfIn PDF document text
    • https://www.cukoyem.com.tr/wp-content/plugins/super-forms/uploads/php/files/3681qtk3iu37ggj45l5aaeqv16/kigadawopi.pdfIn PDF document text
    • http://yachtandgulet.com/userfiles/file/115401513.pdfIn PDF document text
    • http://progfin.pl/userfiles/file/87505601075.pdfIn PDF document text
    • http://chandigarhdatarecovery.com/files/file/96134688180.pdfIn PDF document text
    • http://www.scmphotography.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160c2d9cf16c0d---43773395115.pdfIn PDF document text
    • http://novaserv.com/wp-content/plugins/formcraft/file-upload/server/content/files/160e233357a0db---59383726054.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/LPIa9PGmDLg/uplcv?utm_term=difference+between+servant+and+maidPDF 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_off0000ef4c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF4C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010763.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10763 10764 bytes
SHA-256: 0c3e86934929a173b8ba47ceaa0a57f8ec09da2fa18505f07ba84e30aa1e3cd4
font_02_sfnt_off00012040.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12040 17812 bytes
SHA-256: f23397a788cfa1fc399fc73aaf565545760ae2ace05e84df3e7a95ae91cae018