Malicious PDF — malware analysis report

Static analysis result for SHA-256 7f237a8aa143029c…

MALICIOUS

PDF

94.6 KB Created: 2021-09-02 00:54:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: ea8876d26dfea5be1c261e146001dd13 SHA-1: a6f65d7de470d7d716a1fb0e28afa87136e25317 SHA-256: 7f237a8aa143029c33caad9350534a7a076a90d9b9615db9ea108e6ae110d70d
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories and contains embedded JavaScript. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9938

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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.
  • 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://rybarict.cz/webpagebuilder/ckfinder/userfiles/files/76181423682.pdf In PDF document text
    • https://www.gsccn.it/wp-content/plugins/formcraft/file-upload/server/content/files/160c8b35c58938---wogazunoxesatom.pdfIn PDF document text
    • https://victory-agency.com/wp-content/plugins/formcraft/file-upload/server/content/files/16116fdbecda3b---12710880721.pdfIn PDF document text
    • http://luisacortesearchitetto.it/userfiles/files/67042899666.pdfIn PDF document text
    • http://matonaklawfirm.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/jerovom.pdfIn PDF document text
    • http://tourbusan.net/FileData/ckfinder/files/20210609_AB56DF70B546B1DB.pdfIn PDF document text
    • https://www.pennlighting.com/wp-content/plugins/super-forms/uploads/php/files/7d6accd592ee9d07e666d2e6600b9b9f/39427074787.pdfIn PDF document text
    • http://nebovsem.ru/app/webroot/files/files/waxobexumudosofuvagetud.pdfIn PDF document text
    • https://konferencii.ru/js/ckfinder/userfiles/files/31272418499.pdfIn PDF document text
    • https://auf.vn/wp-content/plugins/super-forms/uploads/php/files/v9inj2g6ju14khp8e7gb93kjp0/zonovazunalobalosezi.pdfIn PDF document text
    • http://www.theflightfest.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609b5ffa83881---lokitewabewuv.pdfIn PDF document text
    • http://linker-apps.com/files/paludibepurafaradu.pdfIn PDF document text
    • http://www.ncstarim.com.tr/wp-content/plugins/super-forms/uploads/php/files/bka2c1dd8masujg0o9tk8qcbm7/fotozubixesetolewa.pdfIn PDF document text
    • https://frontiersneurophotonics.org/wp-content/plugins/formcraft/file-upload/server/content/files/1/16075f51ba4cb3---tixowawewek.pdfIn PDF document text
    • https://purebodycare.courses/wp-content/plugins/super-forms/uploads/php/files/fevvl42m4gsf2sm1ab6u43e8j5/sazezabanivuwesobezo.pdfIn PDF document text
    • https://gbeequestriansurfaces.com/wp-content/plugins/super-forms/uploads/php/files/713a8kkks3i9fsoivophka54s4/punevapumuwesumujewavu.pdfIn PDF document text
    • http://thunderstar.cn/userfiles/file/20210502200153495328055.pdfIn PDF document text
    • https://deltarealestate-eg.com/userfiles/file/13061884187.pdfIn PDF document text
    • https://blackknowledge.com/wp-content/plugins/super-forms/uploads/php/files/7d331dabc1854e4af1828efdd9f5cc71/rukirutuve.pdfIn PDF document text
    • https://k-barrierfree.com/FileData/ckfinder/files/20210706_9D14A71A801F418A.pdfIn PDF document text
    • http://domeinbeverdonk.be/assets/files/file/69744240084.pdfIn PDF document text
    • http://muszempilla.com/files/file/11995635570.pdfIn PDF document text
    • http://miroslaws.com/ckfinder/userfiles/files/puvuzatisawonuwoxuwibop.pdfIn PDF document text
    • http://victoryelectricalsupply.com/ckfinder/userfiles/files/88931958941.pdfIn PDF document text
    • https://ratco-hardware.com/Ups/files/70318417032.pdfIn PDF document text
    • https://www.jahnigterbraak.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160d1cd280c363---golomolobizoxas.pdfIn PDF document text
    • http://boschvietnam.com/files/usersfiles/files/16610818207.pdfIn PDF document text
    • http://herodumpsterrental.com/wp-content/plugins/super-forms/uploads/php/files/7d989e51bf3cfdd3eb5275799a58afb7/givosopemepir.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BkSY9tpko7c/uplcv?utm_term=movie+the+loverPDF 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_off00010e29.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10E29 9828 bytes
SHA-256: 9e94787b6d876114310ec91c7bfb4944ba4583395e779c031414f30231245464
font_01_sfnt_off000123da.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x123DA 18756 bytes
SHA-256: 8be8f7e2c056781f94d7a02663009e8d78bfaf722ce4b5453adeffac6596e47b
font_02_sfnt_off00015427.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15427 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1