Malicious PDF — malware analysis report

Static analysis result for SHA-256 25ce4ea5e3a7765a…

MALICIOUS

PDF

95.3 KB Created: 2021-10-10 04:24:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 318c915f62e9cc00dcc15c5adbf433e9 SHA-1: 00eea67beeceb58291f110478fa81d119dc07375 SHA-256: 25ce4ea5e3a7765af8e28bea3d4b0e6bae77752c48c19d2f21f6deb5d3c03752
156 Risk Score

Malware Insights

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

The PDF file contains a link farm with numerous URLs pointing to various domains, many of which are hosted on compromised CMS uploads or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution. The document body is unreadable, but the heuristic firings and URL analysis confirm the attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9965

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://castrolmintabolt.hu/images/upload/file/tidesobidozoxizodo.pdf
    • http://feldbach-tourismus.at/files/sisuw.pdf
    • https://kildevangen.dk/files/72575140539.pdf
    • http://amicalelaique-guyancourt.fr/ckfinder/userfiles/files/5568058826.pdf
    • https://icnj.net/ckeditor/ckfinder/userfiles/files/60304039916.pdf
    • http://joshuadacosta.com/wp-content/plugins/formcraft/file-upload/server/content/files/16143ce0ccbc5c---38752504408.pdf
    • https://shturnev.com/files/foFKED/file/75153256803.pdf
    • https://agrotehholding.ru/wp-content/plugins/super-forms/uploads/php/files/e0b8b28b0c9babbf6c4e3b74b4e2e2e9/tujijuv.pdf
    • http://dobraukraina.org/sites/all/sites/dobraukraina.org/files/9090365644.pdf
    • https://expobar.vn/app/webroot/files/images/pages/files/75454511435.pdf
    • https://bhandarisurgical.com/ckfinder/userfiles/files/rejekonituxikevupagowavun.pdf
    • http://wildzipper.com/clients/wildzipper/userfiles/file/59502311129.pdf
    • http://rakkhunnursinghome.com/user_img/files/28010357976.pdf
    • http://er-trans.com/img/produkty/files/pedagoxabunivewulo.pdf
    • https://kermanrooz.com/img/files/86837858460.pdf
    • http://www.tenniscanberra.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16155752f197ac---pepovilavogipesuvoxozevum.pdf
    • http://bukharajohnscreek.com/sites/default/files/file/tadifobaxugojamopudafido.pdf
    • http://coming-c.com/userfiles/file/25970034469.pdf
    • http://lhdrum.com/User_File/UpFile/file/20211010072156_NTUzNzEwOTA5NDM=.pdf
    • http://www.domplit2006.ru/ckfinder/userfiles/files/xojokejufuvimapejimekufom.pdf
    • https://abcelectricalonlineshop.brilliantwebtech.com/userfiles/files/12480081497.pdf
    • http://brodart01.com/wp-content/plugins/super-forms/uploads/php/files/dnqlmm53sdfm1k8k7je5uje77o/vepusevilologola.pdf
    • http://collegium-connect.nl/ckupload/files/19374409196.pdf
    • http://wwpokebar.com/uploads/files/4997509643.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/ngfLrbzwjls/uplcv?utm_term=social+science+general+knowledge+questions+answers
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00010a4c.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10A4C 16792 bytes
font_01_sfnt_off00012263.bin
54b0cddb6d0c22a901a081eb3ce92e9611689695440e6fe6189a5677575ce06a
pdf-font-stream PDF embedded font (sfnt) at offset 0x12263 11044 bytes
font_02_sfnt_off00013bbd.bin
e07e668f2c34c502c08b00eb88220e309fa1e09145fcbabc5b2e2af69316792a
pdf-font-stream PDF embedded font (sfnt) at offset 0x13BBD 19700 bytes