Malicious PDF — malware analysis report

Static analysis result for SHA-256 a6f318e5335bf9f7…

MALICIOUS

PDF

156.8 KB Created: 2021-08-22 18:45:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 57b278bc3ddefb9ec37eb5407702ce39 SHA-1: 3c4807a3b02f8486a5dd2ea819f3dbb91e393384 SHA-256: a6f318e5335bf9f7a6fbeaac076681786b1bac85698358b84ff60dd05e0e7cc1
156 Risk Score

Malware Insights

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

The PDF contains a link farm designed to redirect users to various external websites, many of which are hosted on compromised CMS upload directories. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution. The document body is heavily obfuscated and appears to be junk data, offering no direct user-facing content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9851

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://www.ncstarim.com.tr/wp-content/plugins/super-forms/uploads/php/files/a2p8hm725lqas2uvdac5t4kga1/30938007098.pdf In PDF document text
    • https://amartzon.store/wp-content/plugins/super-forms/uploads/php/files/5693985592768115198afb94fc2a6703/zijipokabawudejobib.pdfIn PDF document text
    • http://totaleclipsenv.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a3786a4752f---kiruwedologeze.pdfIn PDF document text
    • https://eltonltd.ru/sites/default/files/uploads/suwapuwomupid.pdfIn PDF document text
    • http://benetalent.com/upload/files/xubapalevibovod.pdfIn PDF document text
    • http://uptownchantilly.com/uploads/files/guworag.pdfIn PDF document text
    • http://erbilsunhotel.com/wp-content/plugins/super-forms/uploads/php/files/9hl9qs5e9ql8p7v4486f8jbj60/wapuwekase.pdfIn PDF document text
    • http://asdgolfclubtoscana.com/writable/public/userfiles/file/20315974942.pdfIn PDF document text
    • https://cloud-tutors.com/wp-content/plugins/super-forms/uploads/php/files/f093d8ef5a8bdc5abef3dfff86f28436/62057750577.pdfIn PDF document text
    • https://mbzl-pro.xyz/web/img/podborky/files/fijezumowu.pdfIn PDF document text
    • https://www.djluk.co.uk/wp-content/plugins/super-forms/uploads/php/files/top6811ia4ic0t3h8lb235o3pf/88057775079.pdfIn PDF document text
    • https://klingende-zeder.de/wp-content/plugins/formcraft/file-upload/server/content/files/160b607b0c54e6---putujopupabi.pdfIn PDF document text
    • http://giovanniseneca.eu/userfiles/files/98502441597.pdfIn PDF document text
    • https://aviseco.ro/userfiles/file/69072155563.pdfIn PDF document text
    • http://www.christinemartin.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160f48aff6760a---pakukezunogijifad.pdfIn PDF document text
    • https://bayardplaza.co.uk/wp-content/plugins/super-forms/uploads/php/files/lhhutdrn28a903d4crbgcg6e7m/76909178805.pdfIn PDF document text
    • http://shhs69reunions.com/clients/e/e9/e92da0bc0099326815942f81a5c18dfc/File/773832330.pdfIn PDF document text
    • https://ehblending.com/wp-content/plugins/super-forms/uploads/php/files/dd47d8904091c37acf4c6e0944d51844/1049604627.pdfIn PDF document text
    • http://zadonskiy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160b8364bd1cd2---22623945398.pdfIn PDF document text
    • http://smeclassof1987reunion.com/clients/37165/File/74903611502.pdfIn PDF document text
    • https://www.quatainvestimentos.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1609ec56c9df01---95452855496.pdfIn PDF document text
    • http://wuxihemei.com/ckfinder/userfiles/files/20210626_022918.pdfIn PDF document text
    • http://townofwinslowin.com/flash/townofwinslowin.com/file/28036261375.pdfIn PDF document text
    • http://agataklimowska.pl/userfiles/file/3741661704.pdfIn PDF document text
    • http://limobebe.com/userfiles/files/59764647879.pdfIn PDF document text
    • http://elyriahigh1974.org/clients/0/05/052ab20d644b737728595af1a47b4450/File/vegajizanamoxetok.pdfIn PDF document text
    • http://hz-kontejnery.cz/ckfinder/userfiles/files/likeramutadise.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3CAf4wW3hvY/uplcv?utm_term=andy+whyment+singing+desperado+linda+ronstadtPDF 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_off0002050e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x2050E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00021d25.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x21D25 11020 bytes
SHA-256: 427be5eb8204646cef6668141c96f2b3a5cc201a35994d38df588f6723de198c
font_02_sfnt_off0002366d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x2366D 17880 bytes
SHA-256: ca01c12639ce547ce8718295f054131a1403388ad4a6ba56397097f357ff1fcc