Malicious PDF — malware analysis report

Static analysis result for SHA-256 f133ee93c9ae9fed…

MALICIOUS

PDF

79.3 KB Created: 2021-09-05 14:53:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: cb067b71b884b57b4299b8386d05227d SHA-1: c4e731d6e7524e425c72326eb0bdaf76deda948f SHA-256: f133ee93c9ae9fedc405d32ed0e55c2ad7c67e8b04bc7ba10949aeeeef3506b5
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics identified it as a link farm, with many URLs pointing to compromised CMS uploads and disposable hosting, suggesting a phishing or malware distribution scheme. Although no scripts were explicitly extracted, the PDF format can embed JavaScript, which could be used to redirect users to these malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://orvosvalaszto.hu/uploads/files/kogadowibir.pdf In PDF document text
    • https://theatresaucinema.fr/uploads/file/76979918726.pdfIn PDF document text
    • https://asigurareingermania.ro/wp-content/plugins/super-forms/uploads/php/files/aa4qk17k8u7qb6djlenqlv10ki/76819265522.pdfIn PDF document text
    • https://forkidsvietnam.vn/wp-content/plugins/super-forms/uploads/php/files/htglp7ebbbjl53u8euac1pbb7c/kidosikanaga.pdfIn PDF document text
    • http://abwingsmd.com/uploads/files/38980738677.pdfIn PDF document text
    • https://hopefor.today/wp-content/plugins/super-forms/uploads/php/files/3921122cde935c4d824380456eebafec/tugewuzuxemojaru.pdfIn PDF document text
    • https://chrmglobal.com/userfiles/file/77203274451.pdfIn PDF document text
    • https://steammining.com/userfiles/file/zikak.pdfIn PDF document text
    • http://chinalabware.es/d/files/xilitolenofis.pdfIn PDF document text
    • http://custom-mugs-factory.com/uploadfile/files/30169937424.pdfIn PDF document text
    • https://fotojursa.cz/userfiles/file/kalavezobago.pdfIn PDF document text
    • https://arenda1s.ru/wp-content/plugins/super-forms/uploads/php/files/d8177d4b9b4c058c931258c33e1c6a0f/sinebunijolojutodilap.pdfIn PDF document text
    • https://blackknowledge.com/wp-content/plugins/super-forms/uploads/php/files/04ec78c34281269656d73f36b393847a/vorugupanuxidojejimuzib.pdfIn PDF document text
    • http://finsura-lifedirect.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1607be3a054eb2---dipab.pdfIn PDF document text
    • https://mamproducciones.es/wp-content/plugins/formcraft/file-upload/server/content/files/16077d89dd74b6---dosemegusa.pdfIn PDF document text
    • http://aeskulap24h.de/wp-content/plugins/formcraft/file-upload/server/content/files/160b5b07e17e49---pimanobixonomujapotipofir.pdfIn PDF document text
    • http://yesilderecine.com/admin/editor_resim/file/tadelof.pdfIn PDF document text
    • http://webinside.pl/userfiles/file/tibakovetuki.pdfIn PDF document text
    • https://sharzh-ufa.ru/wp-content/plugins/super-forms/uploads/php/files/e0bf6057d5d944c41f58dd827348976d/13849728877.pdfIn PDF document text
    • http://chi-kara.net/userfiles/file/rulokebos.pdfIn PDF document text
    • http://pogotowienaukowe.com/Upload/file/9126664199.pdfIn PDF document text
    • https://staffxrecruitment.com/wp-content/plugins/super-forms/uploads/php/files/43b5cf0dfac82845565a84d035081d37/6184626184.pdfIn PDF document text
    • http://olgapolyakova.de/files/files/20125927032.pdfIn PDF document text
    • http://mega-gold.com/userfiles/files/72537564536.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/LPIa9PGmDLg/uplcv?utm_term=merge+pdf+online+no+size+limit+freePDF 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_off0000d23e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD23E 17016 bytes
SHA-256: 1645f69cd0620ea819605ff8ec29b155204011e5faae22c25c950e6763742783
font_01_sfnt_off0000feb3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFEB3 10732 bytes
SHA-256: 5b8a72e6a49f90a1fb18e26811c653c64b1f3dedf42c00b44b313a9ca2f79cac
font_02_sfnt_off00011719.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11719 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1