Malicious PDF — malware analysis report

Static analysis result for SHA-256 26ef2217159e186a…

MALICIOUS

PDF

78.6 KB Created: 2021-07-08 07:45:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: acf69e7a3159b072a2511ecbbf4f9484 SHA-1: 2eeb05ec51837ad1e47692f32cb76cfaf400e174 SHA-256: 26ef2217159e186a8ad1d78c6de8b461dfa3649de8824e29d4fa7de2019ff706
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file functions as a link farm, containing numerous URLs pointing to various domains, many of which appear to be compromised or disposable hosting. The ML classifier strongly indicated maliciousness, and the presence of multiple external URIs suggests an attempt to redirect users to potentially harmful content or phishing sites. Although no scripts were explicitly extracted, the nature of the link farm and the heuristic firings point towards a malicious intent, likely related to distributing malware or facilitating phishing campaigns.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9958

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://synerhu.ru/uplcv?utm_term=the+handbook+of+bilingualism+and+multilingualism
    • https://nbtele.com/en/cache/fck_files/file/gapobodabupiwelu.pdf
    • http://www.deco-interieure.com/userfiles/file/63534693243.pdf
    • https://binhruamuinanobac.com/wp-content/plugins/super-forms/uploads/php/files/u5mm4j6c83ucja28b9oqs3scp9/zukigufel.pdf
    • http://xn--12cm8caae5d9a0a0a1dxk6dd.com/user_img/files/zivaxusi.pdf
    • https://bio-obst-und-gemuese.de/userfiles/file/ganurizupivuxikad.pdf
    • https://www.jahnigterbraak.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160abf24b1fcdb---vevabafosumavusosifur.pdf
    • https://canionglobal.com/FCKeditor/file/42050098031.pdf
    • https://www.ayersworthglen.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606fcb8a85f7e---fuputukojizalapoxajexonen.pdf
    • http://mutitar.com/user_img/files/fubolanegik.pdf
    • https://www.opdrrustukalac.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609b90e98588f---33455091366.pdf
    • http://mikailang.net/userfiles/file/20210508170813_1136038656.pdf
    • http://vudafrique.com/wp-content/plugins/super-forms/uploads/php/files/50ad170a1851abfab556e1bb21440d65/zusalatuzumuminej.pdf
    • https://ukdirectremovals.com/wp-content/plugins/super-forms/uploads/php/files/dcc9bcc8b92d9d9f17c239585e0e3afa/94243789036.pdf
    • https://baoholaodong24.com/userfiles/file/31216211994.pdf
    • http://www.nbrownies.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16076a5787df3f---70134075220.pdf
    • http://marta-galan.com/files/varios/file/35787080286.pdf
    • http://pokemom2.com/uploads/files/71936613562.pdf
    • https://aguiapromocional.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1609680cb19b27---30840661239.pdf
    • https://dpmceramiche.it/file/vavula.pdf
    • http://chnli.tw/CKEdit/upload/files/galigipedibobunetofod.pdf
    • https://raptiherbal.com/ckfinder/userfiles/files/tabodorejuzemajaf.pdf
    • http://summithigh49.com/clients/3/33/3334069ac8a672cbece4a9536eb221cc/File/sevunopapafowabisaxov.pdf
    • http://www.kinoimaging.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160d551e1aa17f---14303179091.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000cdbe.bin
af3c490950ac923451011ad83b96ac73d783d0e89389c86f58007e705b28b9d8
pdf-font-stream PDF embedded font (sfnt) at offset 0xCDBE 10996 bytes
font_01_sfnt_off0000e6d9.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xE6D9 16792 bytes
font_02_sfnt_off0000feeb.bin
f61bb16684a6d597d58d3fe6b24e8e54eb3f77e15469cb136898e1179dcfe9da
pdf-font-stream PDF embedded font (sfnt) at offset 0xFEEB 17152 bytes