Malicious PDF — malware analysis report

Static analysis result for SHA-256 4b057195c3787e03…

MALICIOUS

PDF

77.5 KB Created: 2021-06-29 00:43:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 74f9ed4cc8554903a3fff0ff0e814263 SHA-1: ea04c41bd9c4dfb184477a62cc08fdcc235efbd4 SHA-256: 4b057195c3787e03dfd63ed5957fb06944d4139f49f5c599165ab5666ae37528
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 disposable hosting or compromised CMS upload directories, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution. No scripts were extracted, and the document body was unreadable, so the attack pattern is inferred from the URL analysis and heuristic firings.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9829

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://sunnysideclassof64.com/clients/a/ac/acc4ccb49d7935ca36198347b895393e/File/zazevefaviwaxoba.pdf
    • https://alkalacarservice.com/public_html/userfiles/file/kiramevale.pdf
    • https://vaytieudungtragop.com.vn/wp-content/plugins/super-forms/uploads/php/files/h6lj6oc5oj4jeap491oge5lk26/xikekepixasojon.pdf
    • https://kicksomeglass.com/wp-content/plugins/super-forms/uploads/php/files/b0e455fde4f8dac800535ae6d43ab3c1/somaj.pdf
    • https://cffcommunications.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1/16087180d069ec---vadutiwinewuzizutofegim.pdf
    • http://bezagsecurity.cz/userfiles/94366259861.pdf
    • https://urbanplace.me/wp-content/plugins/super-forms/uploads/php/files/c07a873b897596a217b63159b1fff11e/luwumetusupekijufef.pdf
    • http://asesorialuishervas.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d2304462de5---dizisurupazumuvubaxufa.pdf
    • http://flexicourse.cz/res/file/3562934470.pdf
    • http://thaide.org/userfiles/file/34632888655.pdf
    • http://principessavencanice.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b9f9c4adc80---xerobaxexazafukawusup.pdf
    • http://graficaeformazione.it/userfiles/file/zibedogaseremibimu.pdf
    • https://wccia-vastu.com/wp-content/plugins/super-forms/uploads/php/files/21be6721c7e11e61e932812eaa6cb273/99254947714.pdf
    • https://benchmarktransitions.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607df9a3e1ae4---74685152088.pdf
    • https://mut-zur-veraenderung-hambuch.de/userfiles/file/11916723839.pdf
    • http://midel.me/userfiles/file/kazilumebutope.pdf
    • http://barrarioservicos.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160bb753ae13e2---xunonubelek.pdf
    • http://www.bash.cl/media/file/duremud.pdf
    • https://adbadog.com/wp-content/plugins/super-forms/uploads/php/files/8630906f231128c04d3a36d4af25c37b/8848823878.pdf
    • https://jokerprod.net/userfiles/file/5972032902.pdf
    • http://www.belladermeestetica.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160d5151d31c72---83979966430.pdf
    • http://www.suffaheducation.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a9bd10d3375---bepiniwajofotu.pdf
    • http://chocolatycakes.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607b75b89e16f---ponola.pdf
    • http://kaufdeinauto.de/wp-content/plugins/formcraft/file-upload/server/content/files/1607768d149ef3---76092037798.pdf
    • https://alphaveneers.co.uk/wp-content/plugins/super-forms/uploads/php/files/2aa48d47a6d380f13679bbbe0f43cf55/nirefibusidegugawigu.pdf
    • http://faurerom.com/userfiles/file/14324332089.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/cv9VXjIrmdE/uplcv?utm_term=wordscapes+daily+puzzle+feb+18+2021
    • 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_off0000c921.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xC921 16792 bytes
font_01_sfnt_off0000e133.bin
506193b57193aa42660ab56a4b2995598fdfad454bf35e102d67271d230f33c3
pdf-font-stream PDF embedded font (sfnt) at offset 0xE133 16848 bytes
font_02_sfnt_off00010c37.bin
966768b69ae9010aabe2acc3976a1e6c199b90bd9c26c0a68d9f7caba75402d8
pdf-font-stream PDF embedded font (sfnt) at offset 0x10C37 11320 bytes