Malicious PDF — malware analysis report

Static analysis result for SHA-256 7174208da6aac5c9…

MALICIOUS

PDF

79.9 KB Created: 2021-08-28 12:05:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-29
MD5: 49125d55ae453850ad8b42f68fa60a3e SHA-1: 9472a01aaf8aa82a2869f2cdd4cd4a8b76c6933c SHA-256: 7174208da6aac5c98b39da5ac142d61b82b35cbd8ec86482690267b445aa3ebb
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The heuristics reveal it functions as a link farm, directing users to various compromised websites, some of which host PDF files. This suggests a phishing or social engineering attack aiming to trick users into downloading further malicious content, potentially disguised as a PDF reader update.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9987

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 http://mynigaoe.com/upload/file/20210620172215.pdf In PDF document text
    • http://akgikorea.com/file_upload/fck_upfile/file/64697936481.pdfIn PDF document text
    • http://squarcialupirelaxinchianti.com/writable/public/userfiles/file/45585961931.pdfIn PDF document text
    • http://buffagiuseppeinfissi.com/userfiles/files/83017202556.pdfIn PDF document text
    • http://www.tomasjelinek.com/img/pub/file/zeduwotimelobo.pdfIn PDF document text
    • http://redwoodpwr.com/wp-content/plugins/super-forms/uploads/php/files/p91o7m2tah4d2tv8gvqvib6602/filobazekibar.pdfIn PDF document text
    • http://varadimasszazs.hu/uploads/files/boporujotovuw.pdfIn PDF document text
    • http://metalltechnik-kutschi.at/37784469119.pdfIn PDF document text
    • http://gostium.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b1118c53590---48317267152.pdfIn PDF document text
    • http://www.ambredore.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ac666d47167---35540615239.pdfIn PDF document text
    • https://investmentskillsgroup.com/images/userfiles/file/bomenow.pdfIn PDF document text
    • https://mandalaconfeccao.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16099bd89189cc---35727507290.pdfIn PDF document text
    • http://www.rec39.ru/wp-content/plugins/super-forms/uploads/php/files/734441795cb5c2c746945861a7bd397d/bupikutulibasiw.pdfIn PDF document text
    • http://doo-san.com/userfiles/file/20210516150757.pdfIn PDF document text
    • http://sghscsjamarai.org/guruhargobind/userfiles/file/26435586378.pdfIn PDF document text
    • https://fedico.ca/upload/editor/file/nogunigeninarebik.pdfIn PDF document text
    • http://phs1961.com/clients/2/29/29da8dc1278d8f1c58a3d16208bcb4e7/File/vagax.pdfIn PDF document text
    • https://dollarplus98.com/images/upload/files/mozava.pdfIn PDF document text
    • http://haki.vn/uploads/files/20153025399.pdfIn PDF document text
    • https://wurstfargo.com/wp-content/plugins/super-forms/uploads/php/files/982672a05f54c8aee6df8d3dc6930ad0/62285557107.pdfIn PDF document text
    • http://dzbnf.com/upload/file///jeluf.pdfIn PDF document text
    • http://rencontres-icare.org/userfiles/file/maluzidus.pdfIn PDF document text
    • http://neilreardon.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/satadudanasekoz.pdfIn PDF document text
    • http://mdsalon.ru/img/lib/file/fepise.pdfIn PDF document text
    • https://astdubai.co/userfiles/files/gegevajorenesemotubelufa.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/6naE_Nh8_CY/uplcv?utm_term=pdf+reader+latest+version+for+windows+10PDF 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_off0000cc26.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCC26 10676 bytes
SHA-256: c23fb65ee69cbacd94d9ce30622c6599c6c84aec22f321806e3fdb0e37cbe9cf
font_01_sfnt_off0000e4cf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE4CF 20280 bytes
SHA-256: 34e3226474d42c4bc2f3b7642f02527f724d7c40fbbd16fe192762eda1bbbab0
font_02_sfnt_off000118eb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x118EB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1