Malicious PDF — malware analysis report

Static analysis result for SHA-256 ecc3718a12b304c7…

MALICIOUS

PDF

89.7 KB Created: 2021-08-11 20:42:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 94a0da348de5e92b06ee51b9394addd3 SHA-1: 11b90710147116e9c1b7323c8f22ab4c1403f243 SHA-256: ecc3718a12b304c797fd41b497ff5a3e5aba09c6aa777c5d987f9f96d774c084
96 Risk Score

Malware Insights

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

The PDF document contains a large number of external links, many of which point to compromised WordPress sites. The ML classifier strongly indicates maliciousness, and the overall structure suggests a link farm designed to manipulate search engine results or redirect users to malicious content. No scripts were extracted, limiting the analysis of direct execution vectors.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9972

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://cructi.ru/uplcv?utm_term=what+is+the+point+of+dead+poets+society PDF link annotation
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bbfe9fb7a1c---43368628450.pdfIn PDF document text
    • http://www.majoriscambio.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160afc6fcf1268---78536013933.pdfIn PDF document text
    • https://www.coconutlodge.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d2dcb1db944---61514045508.pdfIn PDF document text
    • https://btsis.com/upload/ckfinder/files/58301285600.pdfIn PDF document text
    • https://www.baptistenhardenberg.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16082e27027a74---sepisuzatirimelotubewi.pdfIn PDF document text
    • http://www.zopfitravel.com/wp-content/plugins/formcraft/file-upload/server/content/files/160f17089663b8---67666544570.pdfIn PDF document text
    • http://cambresisemploi.fr/ckfinder/userfiles/files/37510822396.pdfIn PDF document text
    • https://www.booster-p.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c53c0441548---21730253493.pdfIn PDF document text
    • https://o-dance.com/upload/files/xuxirekexomof.pdfIn PDF document text
    • http://tiszaikaland.hu/upload/file/48489172517.pdfIn PDF document text
    • http://allnatureint.com/userfiles/file/bitinoriwabitirikokuz.pdfIn PDF document text
    • http://happysmilecard.com/uploads/files/bixekovivekivetefu.pdfIn PDF document text
    • http://1hozain.ru/files/userfiles/files/40014220994.pdfIn PDF document text
    • http://www.ambredore.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a149beee293---24680294819.pdfIn PDF document text
    • http://www.hkqi.com/wp-content/plugins/formcraft/file-upload/server/content/files/16089efa8614b7---87289352453.pdfIn PDF document text
    • https://yellowstonewildlife.com/liritas.pdfIn PDF document text
    • http://hytechplus.com/userfiles/file/libonagumifuxovido.pdfIn PDF document text
    • https://infiniteprospects.com/FCKeditor/file/misot.pdfIn PDF document text
    • http://www.supair-lux.hu/ckfinder/userfiles/files/66868308585.pdfIn PDF document text
    • http://limpiasol.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d7b92e9ba47---95774154701.pdfIn PDF document text
    • http://starrwindow.com/clients/863399/File/6151476113.pdfIn PDF document text
    • https://yingzhaoliuart.com/upload/file/7230260922.pdfIn PDF document text
    • https://confetti-seasons.ru/upload/files/96553219802.pdfIn PDF document text
    • http://gibisch.info/files/files/dekoxavigemetuwepaju.pdfIn PDF document text
    • http://gphs100.com/clients/e/e3/e3ed30f4e85b1ff1e74f61348c82e8eb/File/38890868075.pdfIn PDF document text
    • 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_off0000f92a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF92A 17052 bytes
SHA-256: a1dac5461e0090e7d1ed9891155c49ee95e4887b74cb4181211bb209f72d1834
font_01_sfnt_off00012558.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12558 10680 bytes
SHA-256: 47c0ef33a961f9ecd9bd2bc32d5865008ba1f8914def77620b403b293485428e
font_02_sfnt_off00013ddf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13DDF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1