Malicious PDF — malware analysis report

Static analysis result for SHA-256 1f4be647d5c6786a…

MALICIOUS

PDF

84.9 KB Created: 2021-06-25 21:58:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: 259993bae48872aeb5be1c23c6a95bd6 SHA-1: e9dd779eedbc6435310d52994d779f3ba3a13311 SHA-256: 1f4be647d5c6786a85b6faf89207a201df796c480b10ad4aea2a829013e1fff6
104 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript, which is a common technique for executing malicious code. It also features a link farm pointing to multiple compromised WordPress sites and disposable hosting, suggesting an attempt to obscure the final malicious destination. The ML classifier strongly indicates maliciousness, and the combination of these factors points to a phishing or malware delivery scheme.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

Heuristics 6

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://avtoarka.ru/wp-content/plugins/super-forms/uploads/php/files/f3c53a0323f5970c07d5f8f6e4728932/87508345663.pdf In PDF document text
    • https://reaga.net/js/ckfinder/userfiles/files/80933220660.pdfIn PDF document text
    • http://millecolori.it/images/file/ladorimeboxuvaposiwotu.pdfIn PDF document text
    • https://lastcallslc.com/wp-content/plugins/super-forms/uploads/php/files/29c5e339a0363953e6bd2b368d823314/67010635161.pdfIn PDF document text
    • http://baohanhranghm.com/upload/img/files/daberibulaminanul.pdfIn PDF document text
    • http://matstravel.ru/userfiles/file/jigujobevetuz.pdfIn PDF document text
    • http://kazenergy.kz/wp-content/plugins/formcraft/file-upload/server/content/files/16084722a94cf5---wopuxejurapena.pdfIn PDF document text
    • http://www.luminicaambiental.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ad50218797b---56103467698.pdfIn PDF document text
    • https://kalatranslation.co.uk/wp-content/plugins/super-forms/uploads/php/files/t96l9r4ckrmmvoe3cdu29hl1c2/29702227219.pdfIn PDF document text
    • http://antik-cafe-bergen.de/wp-content/plugins/formcraft/file-upload/server/content/files/1609f4b75c47cd---fefavemeja.pdfIn PDF document text
    • http://dmhu.eu/uploads/uplib/file/nelesefadelagunusan.pdfIn PDF document text
    • http://salukool.ee/upload/userfiles/file/6001271993.pdfIn PDF document text
    • http://ilyxrace.com/userfiles/files/27152861439.pdfIn PDF document text
    • https://www.opdrrustukalac.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a98dbc56b1f---kenikatazatudaferelaga.pdfIn PDF document text
    • http://susutour.com/userfile/file/mumutunik.pdfIn PDF document text
    • https://marljivo.hr/userfiles/file/59410037537.pdfIn PDF document text
    • https://www.elektrobetrieb-scholz.de/wp-content/plugins/formcraft/file-upload/server/content/files/1606cba7237938---ranitumakubisupega.pdfIn PDF document text
    • https://www.lang-mayer.de/wp-content/plugins/formcraft/file-upload/server/content/files/160a03321887cb---ginija.pdfIn PDF document text
    • http://www.caribbeandentist.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606e4002796d4---53049466437.pdfIn PDF document text
    • https://www.edutechusa.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a3b8b917720---92968460585.pdfIn PDF document text
    • http://www.tenniscanberra.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160909ab237927---98281031481.pdfIn PDF document text
    • http://sad-azov.ru/wp-content/plugins/super-forms/uploads/php/files/1db50054a707eacb1c02ab137f6c71bf/79003869041.pdfIn PDF document text
    • http://meteosputnik.ru/userfiles/file/39181552259.pdfIn PDF document text
    • https://www.harasportcenter.com/wp-content/plugins/super-forms/uploads/php/files/5aoh1ekh5lis5bva3782c502oa/92830554505.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/BkSY9tpko7c/uplcv?utm_term=difference+between+malloc+and+callocPDF link annotation
    • http://e1pl2.nazwa.pl/busy/fotki/file/bigawefe.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_off0000e69c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE69C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000feb3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFEB3 10696 bytes
SHA-256: 430726d1fcd3b3c9cdff87e746ca79640322e149277e9666973f5c582a0fdbf6
font_02_sfnt_off00011746.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11746 17780 bytes
SHA-256: 0dff680445a3cddb825a49d12552e98a3d99f2168fa42ae8dffb6847d969d9ac