Malicious PDF — malware analysis report

Static analysis result for SHA-256 748108adcc5dd41c…

MALICIOUS

PDF

81.9 KB Created: 2021-09-18 10:20:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: f330f69fa93a6309b4ff971c0c02af89 SHA-1: 31d490f258a0ec5a36dd9187c4ce38a623578688 SHA-256: 748108adcc5dd41ca64bc8fe70ac9df3fc1a14e8b662afd4c019ceb16bede8a6
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains numerous embedded URLs, with one heuristic specifically identifying it as a link farm on disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The sample's structure and the presence of multiple unknown-reputation URLs suggest it's part of a campaign to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://drumlockingclamp.com/FCK_Editor_Images/files/fufedojasofijof.pdf In PDF document text
    • https://anukulagrotech.com/userfiles/file/selosi.pdfIn PDF document text
    • https://btsis.com/upload/ckfinder/files/jugijad.pdfIn PDF document text
    • https://jdsliquorlocker.com/nbloom/fckuploads/file/fifadunijupokalaxit.pdfIn PDF document text
    • https://srmhomes.com/images/bulk_images/files/furod.pdfIn PDF document text
    • http://mskgroup-spb.ru/upload/file/53095423712.pdfIn PDF document text
    • http://malbreil.com/userfiles/file/lusifiwu.pdfIn PDF document text
    • http://bjbtrh.com/files/pic/file/31222060873.pdfIn PDF document text
    • http://bige.vn/uploads/userfiles/file/75241910390.pdfIn PDF document text
    • http://global-leasing-management.com/uf/file/bugofipexojinivo.pdfIn PDF document text
    • https://www.physioaktivkramer.de/wp-content/plugins/formcraft/file-upload/server/content/files/161443abd2371e---32978220784.pdfIn PDF document text
    • https://montpellier-business-plan.com/mbp/upload/images/images/upload/ckfinder/72498486171.pdfIn PDF document text
    • https://edenestates.com/ckfinder/userfiles/files/45051475110.pdfIn PDF document text
    • https://oteaexpert.fr/cite_imgs/file/84100164105.pdfIn PDF document text
    • https://alismobile.co.uk/wp-content/plugins/super-forms/uploads/php/files/8d43c2869a2110f5316abc1204a5d19f/dofadupuxuwogasikufojoze.pdfIn PDF document text
    • https://curvy.tw/upload/files/959100058.pdfIn PDF document text
    • https://flyags.com/editorResources/file///56852357181.pdfIn PDF document text
    • https://maconlux.ovh/userfiles/files/97835050151.pdfIn PDF document text
    • http://arc-en-cielproduce.com/ckfinder/userfiles/files/gamomapovetiwoleb.pdfIn PDF document text
    • http://chukgoobok.com/files/fckeditor/file/20860009377.pdfIn PDF document text
    • http://1-cities.com/blog_images/blog_/file/gelopijafozejupipolir.pdfIn PDF document text
    • http://mywayrtk.org/userfiles/file/dodikino.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/YTWXjIUwRh0/uplcv?utm_term=easy+way+to+play+d+chord+on+guitarPDF 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_off0000d8a1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD8A1 18572 bytes
SHA-256: b8d0506aefb1e697b024f22525b710cf43ed6e7c2df343363c9230be45ceefab
font_01_sfnt_off0001083e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1083E 10944 bytes
SHA-256: aba2e991a08fb9c57907e65b97a88b012d056cbaa7b60277292373c7e13c1e31
font_02_sfnt_off0001216c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1216C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1