Malicious PDF — malware analysis report

Static analysis result for SHA-256 51cfa088ea64ebe6…

MALICIOUS

PDF

73.1 KB Created: 2021-09-15 09:37:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 704f1f6c8102343c657551b6b95d9139 SHA-1: 46b12eae4ee63846c10048eb5dae3df856484580 SHA-256: 51cfa088ea64ebe685fc50064a184c6b743a4b3d77f6e3c5c6aca8bd350db9e9
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external URIs and link farms hosted on potentially compromised or disposable domains, indicating a phishing or malware distribution attempt. The ML classifier and ClamAV detection strongly suggest malicious intent. Although no scripts were explicitly extracted, the PDF structure and embedded links are indicative of techniques used to redirect users to malicious sites, likely for credential harvesting or further payload delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9982

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://crysiq.ru/uplcv?utm_term=speed+post+delhi+contact+number PDF link annotation
    • http://daiichilogistics.com/uploads/news_file/lametuxazulo.pdfIn PDF document text
    • http://jpind.pl/userfiles/file/dekulata.pdfIn PDF document text
    • https://www.frankcapassoandsons.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613cda18de155---jegukanivogofada.pdfIn PDF document text
    • http://namlinhchisapa.com/userfiles/image/file/sodutikawiv.pdfIn PDF document text
    • http://ukwoodrecycling.com/userfiles/files/75364723425.pdfIn PDF document text
    • https://mkycc4.com/kycc4.com/userfiles/files/vofafituxuvawiru.pdfIn PDF document text
    • http://www.vegagastro.pl/upload/file/kadux.pdfIn PDF document text
    • https://www.bountyvacation.com/wp-content/plugins/formcraft/file-upload/server/content/files/161325fb389314---zanawidufigunabakimazatu.pdfIn PDF document text
    • http://www.kissdocs.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16138b39d19d9b---jevusaloje.pdfIn PDF document text
    • https://ntiverification.com/userfiles/file/jemojexipebaxateduwugame.pdfIn PDF document text
    • http://kolaykanal.com/userfiles/files/81809778900.pdfIn PDF document text
    • http://jamalcar.com/userfiles/file/27540959746.pdfIn PDF document text
    • https://karpataljaturizmus.hu/upload/tadutamovunudupulix.pdfIn PDF document text
    • http://sushiosushi.com/uploads/files/60224820908.pdfIn PDF document text
    • https://cananalimdar.com/wp-content/plugins/super-forms/uploads/php/files/j4gti1ad5el2lhkqoq94gk0m3l/zawokukefesenitejadu.pdfIn PDF document text
    • https://www.webhisto.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/16140bb7c65aad---moribenusodipisabon.pdfIn PDF document text
    • http://ryyw.com/upload/files/2021/09/202109011051043052.pdfIn PDF document text
    • https://rosebankprimary.co.za/inc/ckfinder/userfiles/files/22914620871.pdfIn PDF document text
    • http://italianopizzeria-pg.com/uploads/files/jekodi.pdfIn PDF document text
    • https://www.shopveriamici.com/wp-content/plugins/super-forms/uploads/php/files/qthjlkl4mf5ltu65i0dotl7i7c/66185883233.pdfIn PDF document text
    • http://mail.me.ntou.edu.tw/ckfinder/userfiles/files/20210914_002249.pdfIn PDF document text
    • http://ciarajewellery.com/editor_upload/file/labupusajuxetutozax.pdfIn PDF document text
    • http://www.zywawiara.pl/pliki/gezatimesitib.pdfIn PDF document text
    • http://pbpharm.com/upload/files/1674468055.pdfIn PDF document text
    • http://dynamicyunnan.com/ckfinder/userfiles/files/76309798420.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_off0000ba09.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBA09 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d21b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD21B 16716 bytes
SHA-256: d764a49fecac6d3964318470ba8f3eeb2d2f65865fe47d0ac469c788f071275d
font_02_sfnt_off0000fd66.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD66 11092 bytes
SHA-256: af6e3a596692297ef008ef82e566465304bf8bc1ecc3e18bcb435315479f189f