Malicious PDF — malware analysis report

Static analysis result for SHA-256 dab82f5a77e8c47a…

MALICIOUS

PDF

81.7 KB Created: 2021-09-04 16:14:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: afb83c19817436487ad78341611c7de3 SHA-1: f2b0c0dcb2df9678c5e532efffdeb477247f516f SHA-256: dab82f5a77e8c47ae41d81b050f08179931900c39c188d6eff0af57655d59695
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs that form a link farm, directing users to potentially malicious sites. Heuristics indicate these links are used for SEO poisoning and point to compromised upload storage, suggesting a phishing or malware distribution scheme. The ML classifier and ClamAV detection strongly indicate malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://polyalpan.hu/_user/file/72166147100.pdf In PDF document text
    • http://bekkercoon.ru/ckfinder/userfiles/files/paxilenijufebubekapixomo.pdfIn PDF document text
    • https://www.frontierexim.com/wp-content/plugins/super-forms/uploads/php/files/2k30mg2gtk3gpa3kcac9i29n0c/55177383171.pdfIn PDF document text
    • https://sgicorp.com/userfiles/files/98438714482.pdfIn PDF document text
    • http://tksvolga.ru/userfiles/file/25508241725.pdfIn PDF document text
    • https://dispomydeal.com/wp-content/plugins/super-forms/uploads/php/files/5d6b2fba2a18d3f55f547a97a6f816c5/47879198127.pdfIn PDF document text
    • http://noithatdangcap.vn/app/webroot/uploads/files/38713413028.pdfIn PDF document text
    • https://ropaalmayoreo.com/images/userfiles/file/tupipobimas.pdfIn PDF document text
    • https://aquaticlandscape.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a85d4607621---68964381780.pdfIn PDF document text
    • https://www.frankcapassoandsons.com/wp-content/plugins/formcraft/file-upload/server/content/files/160acec3856cc1---32990036814.pdfIn PDF document text
    • https://bluebeakbranding.com/wp-content/plugins/super-forms/uploads/php/files/55495f038fa8f08beb93aba170035442/sabanukeresel.pdfIn PDF document text
    • https://www.toptalentusa.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607628abb13f1---69633707375.pdfIn PDF document text
    • http://xn--e1aaafipco3bk8gra3b.xn--p1ai/upload_picture/file/wotetis.pdfIn PDF document text
    • http://nhatminhtrading.vn/app/webroot/uploads/files/46049902957.pdfIn PDF document text
    • http://miltonhigh65.com/clients/874455/File/63310066471.pdfIn PDF document text
    • https://www.groupenahno.com/wp-content/plugins/super-forms/uploads/php/files/lnh0t4g7jladiejd5106l5u6ds/12373644522.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/YTWXjIUwRh0/uplcv?utm_term=chemical+reduction+method+for+synthesis+of+nanoparticles+pdfPDF 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_off0000d8df.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD8DF 17828 bytes
SHA-256: ec74b760c80e461db5bd1c6d44750d671c4f818419641de38055420dabd26186
font_01_sfnt_off0001074b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1074B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011f62.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11F62 11132 bytes
SHA-256: dfb93c8b808a2306bbfecb068c50c6f01933541dcb2be6f7abd28ea937502d47