Malicious PDF — malware analysis report

Static analysis result for SHA-256 4085645be1ff98a5…

MALICIOUS

PDF

80.9 KB Created: 2021-09-15 23:20:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: b68aad34a7fdce5b1cffec780fed9899 SHA-1: c519b17a25a8ffe0bca9334d41c01154d4fa8a15 SHA-256: 4085645be1ff98a54af1ac3863101e6e40967c4373641d269a55b9d873574c8b
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.001 User Execution: Malicious Link

The PDF file contains numerous embedded URLs, many of which point to compromised websites or link farms. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The presence of multiple external URIs and link farms suggests a coordinated effort to redirect users to potentially harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://huntic.ru/uplcv?utm_term=play+store+app+install+for+free PDF link annotation
    • https://www.sidertest.it/wp-content/plugins/formcraft/file-upload/server/content/files/161409146c70fa---24937490757.pdfIn PDF document text
    • http://solarexperte.ch/fckeditor/editor/images/file/29690442792.pdfIn PDF document text
    • http://quiltingacademy.com/fckeditor/userfiles/file/busupis.pdfIn PDF document text
    • http://joyerialaplaza.com/ckfinder/userfiles/files/36327553664.pdfIn PDF document text
    • http://rayer.cn/d/files/14306551625.pdfIn PDF document text
    • https://www.sgestrecho.es/wp-content/plugins/formcraft/file-upload/server/content/files/161371dc354345---gepesesa.pdfIn PDF document text
    • http://phongkhamthienhoa.org/images/files/12392064740.pdfIn PDF document text
    • http://leeclinic.kr/userData/board/file/34706555942.pdfIn PDF document text
    • http://maudchristan.nl/ckfinder/userfiles/files/xazeduxo.pdfIn PDF document text
    • http://textingrights.com/userfiles/files/gonufiluxewalebusul.pdfIn PDF document text
    • https://pasarantogel2.com/contents/files/xugatajusubesutolijuru.pdfIn PDF document text
    • http://pescepiana.eu/userfiles/files/61462425061.pdfIn PDF document text
    • https://amatnieks.lv/pictures/image/xusuzomerowa.pdfIn PDF document text
    • https://www.mozartcantat.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16140ea09c6b58---80251556657.pdfIn PDF document text
    • https://torbay.ru/images/uploads/file/xetimeviwur.pdfIn PDF document text
    • http://eskuvoiiranytu.hu/blog/file/memokevusabuwus.pdfIn PDF document text
    • http://wujipacking.tw/upload/files/raziwavos.pdfIn PDF document text
    • http://amsasecretariat.fr/userfiles/file/31481748196.pdfIn PDF document text
    • http://lexprikson.com/admin/style/images/userfiles/file/51565907725.pdfIn PDF document text
    • http://artio.pl/files/files/21730006858.pdfIn PDF document text
    • https://k-barrierfree.com/FileData/ckfinder/files/20210903_9F8F77E51F4B33E6.pdfIn PDF document text
    • http://king-tableware.com/uploads/files/202109121957348080.pdfIn PDF document text
    • http://dejede.com/userfiles/file/mebagegukigenigaza.pdfIn PDF document text
    • http://globalcenterhotels.com/bot/ckfinder/uf/files/lufebibo.pdfIn PDF document text
    • 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_off0000d8c0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD8C0 10464 bytes
SHA-256: 6447dfabd71e21c78a476a2682b0d60dba1579d19f95f095b0d8dccf605b36d0
font_01_sfnt_off0000f0b1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF0B1 17468 bytes
SHA-256: 426f52a3f1985f37913a1f64c9dda4ac7ca1b1a6323b026c3285ac05b8d6e17c
font_02_sfnt_off00011dcd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11DCD 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1