Malicious PDF — malware analysis report

Static analysis result for SHA-256 23877d5bd93f0d38…

MALICIOUS

PDF

75.7 KB Created: 2021-08-10 07:13:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: c8106ebac8f900ebcb1e0659910109bf SHA-1: 125f52f403ba1916a200b5ae8d7dfa4ab57b5f17 SHA-256: 23877d5bd93f0d3872568dfa4369914c20ab5770711e17e6bcb4e6e09e270080
156 Risk Score

Malware Insights

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

The PDF contains numerous links, many pointing to compromised websites or disposable hosting, indicative of a link farm used for phishing or malware delivery. The ML classifier and ClamAV detection strongly suggest malicious intent. The presence of external URIs and compromised CMS upload links further supports this assessment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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://guineaservicesproviders.com/gsp/files/zugizuzajariwum.pdf
    • http://www.ocptecnology.com/admin/uploaded/fck/file/lebevidilopexoxel.pdf
    • http://cedresarquitectura.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d432c343d5f---765065339.pdf
    • http://drvision.org/wp-content/plugins/formcraft/file-upload/server/content/files/160730b5fea18d---66914080434.pdf
    • http://say-international.eu/userfiles/file/vuzuzifatonigalevigel.pdf
    • http://alliance-ic.ru/uploads/file/buxojadiviteperuzaxoz.pdf
    • http://becucci.it/userfiles/files/41945137077.pdf
    • https://eyetracking.pl/userfiles/file/27966938359.pdf
    • http://mamnonhieutrung.edu.vn/ckfinder/userfiles/files/60637759762.pdf
    • http://www.birapart.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c5bb7abb6a3---84707971933.pdf
    • https://www.dyna-tech.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1607f9bd410b61---zurekefolonokotijuda.pdf
    • https://ncfouting.com/wp-content/plugins/formcraft/file-upload/server/content/files/16096bf75d93ac---zonavudoreg.pdf
    • https://grupo-kayros.com/userfiles/file/zavidovomotumizosigaxunu.pdf
    • http://www.catalogodecineargentino.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a46d4e25aa5---99467950002.pdf
    • http://daonshop.com/files/fckeditor/file/52514633724.pdf
    • https://kakvkusno26.ru/wp-content/plugins/super-forms/uploads/php/files/e3e7364db1ac692ea22698c26547b6aa/49836300712.pdf
    • http://headlinesdinerla.com/uploads/files/pogezomigujebevewuxi.pdf
    • https://www.hungarianassociation.com/wp-content/plugins/formcraft/file-upload/server/content/files/160dc31f4806fe---60409556533.pdf
    • https://expresstestingatl.com/wp-content/plugins/super-forms/uploads/php/files/fe8760044efcf81d10d7baf8ffdc85e6/zagamogelavodajen.pdf
    • http://www.kzhep.in.ua/wp-content/plugins/super-forms/uploads/php/files/fbvtq4svh1tugtt9a4ritojhp5/94815977495.pdf
    • http://limuzine.md/userfiles/file/149997217.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/cv9VXjIrmdE/uplcv?utm_term=rafael+orozco+el+idolo+novela+capitulo+15+completo
    • 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_off0000c038.bin
d87ed47298dc4e3a2dfd489b6e80b4bd4e3bfae65c5cb1bdb6bd11df5a23072c
pdf-font-stream PDF embedded font (sfnt) at offset 0xC038 11068 bytes
font_01_sfnt_off0000da1a.bin
03079ce4a11766e54907360b14bb6e140a9147c59007a1af564cb81c49a9585b
pdf-font-stream PDF embedded font (sfnt) at offset 0xDA1A 17948 bytes
font_02_sfnt_off00010681.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10681 16792 bytes