Malicious PDF — malware analysis report

Static analysis result for SHA-256 213bc23dfd092935…

MALICIOUS

PDF

99.1 KB Created: 2021-07-18 12:43:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: f38231618e297eccadb037eb98180d24 SHA-1: 66aec47b1a9ba3bec06df464bd9aad5688432d17 SHA-256: 213bc23dfd09293512dd4840c8593bfff237a920b2af9a9068f8345ebea34623
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file contains a link farm with numerous URLs pointing to compromised CMS upload directories, indicating a malicious intent to redirect users. The ML classifier also flagged this PDF as malicious. The primary purpose appears to be directing users to potentially harmful content hosted on these compromised sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9739

Heuristics 5

  • 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://limpjet.com.br/wp-content/plugins/super-forms/uploads/php/files/ada23d9ff8f5144d9355899805c258f9/46466053639.pdf
    • https://binarbaidequipment.com/public_html/userfiles/file/juruna.pdf
    • http://ohsongpharm.com/ckfinder/userfiles/files/53484668291.pdf
    • http://ecbpolska.pl/wp-content/plugins/super-forms/uploads/php/files/682750466b6f243f2d505367470e2c06/72140888306.pdf
    • https://fermuar.com/wp-content/plugins/formcraft/file-upload/server/content/files/160adc4e2c8d74---guzoreneges.pdf
    • http://hoacanh.net/luutru/files/96411567862.pdf
    • https://mygamedaysports.com/wp-content/plugins/super-forms/uploads/php/files/e0955412783d09f195a90ee4af89f2ef/32139186168.pdf
    • http://bascobrunswick.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160d67ef66a5e2---36169355118.pdf
    • https://www.acptechnologies.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608085ca7ee82---jafudesavofeverazubawarim.pdf
    • https://senfina.top/uploads/files/84241888663.pdf
    • https://www.physioaktivkramer.de/wp-content/plugins/formcraft/file-upload/server/content/files/1608fa193b27a1---30331647185.pdf
    • http://ck-tct.ru/userfiles/file/serig.pdf
    • http://abnicum.com/files/file/80547268882.pdf
    • http://valeneighbors.com/userimages/93421451211.pdf
    • http://tsg-vaganovskoe.ru/ckfinder/userfiles/files/41178763516.pdf
    • https://www.edutechusa.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a3b8b917720---92968460585.pdf
    • http://svs-pm.com/wp-content/plugins/formcraft/file-upload/server/content/files/160956cd11a8f9---63365974349.pdf
    • https://esteticarcare.com/wp-content/plugins/super-forms/uploads/php/files/13eb69b9bc6244cb3b7c5b0eb17b67f1/mewufugewulegofosaviso.pdf
    • https://aliencosmicexpo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608f1aaeb2fc3---ganomudiziwarumola.pdf
    • http://www.korayozelguvenlik.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ab070b2aa6b---35281998518.pdf
    • https://www.bluegreenshouseboats.in/wp-content/plugins/formcraft/file-upload/server/content/files/160cd6121052b1---80876998771.pdf
    • https://securitydm.com/slicice/file/vuvelo.pdf
    • http://webscape.co.bw/wp-content/plugins/formcraft/file-upload/server/content/files/160a230af1dc7b---naluwuwak.pdf
    • https://solarconsulting.org/wp-content/plugins/super-forms/uploads/php/files/3f913e9a5b4137ada1c693ed11d6dae1/92652276369.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/DOqCt-cVA4I/uplcv?utm_term=what+does+appositive+mean+in+english
    • 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 5

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f760.bin
e167bf0f3d2c9c8b9ccdad4a9be6c082f06a82d84d731fe604c4f3540acc3c60
pdf-font-stream PDF embedded font (sfnt) at offset 0xF760 2132 bytes
font_01_sfnt_off00010127.bin
68f8454b81dea066cd959fb978a34a201b074c13a9a850fd298220f218062a99
pdf-font-stream PDF embedded font (sfnt) at offset 0x10127 10796 bytes
font_02_sfnt_off000119a6.bin
577ab1e86dd6ed5850c5e40a46d32d0603696c739478794a25df26c1757a0b1e
pdf-font-stream PDF embedded font (sfnt) at offset 0x119A6 20212 bytes
font_03_sfnt_off00014e85.bin
b9101d0bc040308de69588c418c16bad83a5d49edba6bb30565c57f4ff8b628d
pdf-font-stream PDF embedded font (sfnt) at offset 0x14E85 16516 bytes
font_04_sfnt_off00016595.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x16595 16792 bytes