Malicious PDF — malware analysis report

Static analysis result for SHA-256 277887f961dab18a…

MALICIOUS

PDF

79.1 KB Created: 2021-09-06 00:20:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: d312962100b171cdd1693e492257209c SHA-1: 4e2005262374f90bc05c0ef49e8bcb4db147535a SHA-256: 277887f961dab18ac1a9f4d93586bd3e3bb31a76da402b17ac10e674dbca67be
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Multiple heuristics point to the PDF acting as a link farm, directing users to various compromised websites and disposable hosting. The presence of numerous unknown URLs suggests a phishing or malware distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9917

Heuristics 6

  • 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.
  • 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://samsungklima.net/upload/ckfinder/files/musuzefixenar.pdf In PDF document text
    • https://pet-fashion.ro/mm/file/45700290856.pdfIn PDF document text
    • https://kamber.dk/wp-content/plugins/super-forms/uploads/php/files/7cfffadb9e26a6830e076a1e0fd2bb94/fibawowasi.pdfIn PDF document text
    • http://xn--80aafkqcanfpgnhbng3b5i9a.xn--p1ai/pict/file/neliw.pdfIn PDF document text
    • https://mokshadhamnepal.org/userfiles/files/51319200226.pdfIn PDF document text
    • http://itfkarnataka.com/cvsprojects/SSK/Source/2.0.0/images/files/dusijogumiveritamidabuze.pdfIn PDF document text
    • https://ivanamihic.com//files/wogunu.pdfIn PDF document text
    • http://midiabyz.com/wp-content/plugins/super-forms/uploads/php/files/7117c47116c82fe9d19b1407f430d3f9/61629048739.pdfIn PDF document text
    • https://deconkhoemanh.com/wp-content/plugins/super-forms/uploads/php/files/nj1k3uercfkmlkpdv5b3augmgb/61058296988.pdfIn PDF document text
    • http://dieta-plus.pl/userfiles/file/wozafid.pdfIn PDF document text
    • http://fantasypartyentertainment.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607ff9c0594d1---zugekowepomowisabawu.pdfIn PDF document text
    • https://hyundainhapkhau.vn/upload/files/ligogu.pdfIn PDF document text
    • http://cuhs1981.com/clients/8/82/82ca37c076ec4232796cb58ed009bb3a/File/monivajevusuza.pdfIn PDF document text
    • http://mjsolankifoundation.com/fck/imagesfile/fodeboxiraloda.pdfIn PDF document text
    • http://vipnjl.com/userfiles/files/buxuravezofipeme.pdfIn PDF document text
    • http://antik-cafe-bergen.de/wp-content/plugins/formcraft/file-upload/server/content/files/1607078eb2f17a---kujopifuxetelibotepur.pdfIn PDF document text
    • https://akdenizokullari.k12.tr/wp-content/plugins/super-forms/uploads/php/files/emu1ivbbfipjijroukkuo9frm7/73064999085.pdfIn PDF document text
    • https://sg-design.top/wp-content/plugins/super-forms/uploads/php/files/a9902855a56b83de638de11649cbd857/80180221372.pdfIn PDF document text
    • http://irmascaritasdejesus.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/160820df0d989f---49833463140.pdfIn PDF document text
    • https://cungcapthitdetuoi.com/app/webroot/files/images/pages/files/45654683881.pdfIn PDF document text
    • https://kuechentreff-schmid.de/wp-content/plugins/super-forms/uploads/php/files/a7kdoj729eb25vc1olaur18rmi/59884794154.pdfIn PDF document text
    • http://www.saveurspoitoucharentes.com/admin/ckfinder/userfiles/files/39150604539.pdfIn PDF document text
    • https://aakritidigitals.com/userfiles/files/37623030272.pdfIn PDF document text
    • https://lakeshoresmilesdentistry.com/wp-content/plugins/super-forms/uploads/php/files/rkpgvvgjitk7jb73ap3gpoo0o4/bikabegisufore.pdfIn PDF document text
    • https://spectrumohio.com/wp-content/plugins/super-forms/uploads/php/files/02141fb62d721b2292004b73be604740/wakeda.pdfIn PDF document text
    • http://yaeram.com/userData/board/file/57183730764.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1xuhb7AK25c/uplcv?utm_term=automatic+water+dispenser+project+pdfPDF 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_off0000cef9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCEF9 11032 bytes
SHA-256: 67e7e42906888d7b6d4384456953c86140f46e682acba4057e882d46abe18ccc
font_01_sfnt_off0000e8b0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE8B0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000100c2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x100C2 17416 bytes
SHA-256: 45fa8a7f3411cccd5b439d7e35259e3e646f7227cc915dfd46a9cb0c37a3edce