Malicious PDF — malware analysis report

Static analysis result for SHA-256 bf86333ef5096329…

MALICIOUS

PDF

85.4 KB Created: 2021-08-18 07:57:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-23
MD5: cf11da2c3f351f6cafffc1e821154672 SHA-1: 16dfc010452c9ba9e96cf19d41d726e1e0405fe4 SHA-256: bf86333ef509632990f8293f2217ae585860c04f38712a3c45a4c5787ffb51eb
104 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF contains an embedded JavaScript stream and a large number of external URIs, many of which point to compromised websites. The ML classifier strongly indicates maliciousness. The embedded JavaScript likely attempts to exploit vulnerabilities or redirect the user, while the link farm serves as a lure to potentially malicious content or phishing pages.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 6

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://singaporeroadshow.com/wp-content/plugins/super-forms/uploads/php/files/b6da7136ca1f9dfd1e21423315238e6e/raxedamabew.pdf In PDF document text
    • http://arisutour.com/ckupload/files/57013366190.pdfIn PDF document text
    • http://kaufdeinauto.de/wp-content/plugins/formcraft/file-upload/server/content/files/1610cd72eba91c---sixeropotidise.pdfIn PDF document text
    • http://bolt.fo/public_html/userfiles/files/padubotevutekuli.pdfIn PDF document text
    • https://brusroom.com/wp-content/plugins/super-forms/uploads/php/files/5f60f849e6080a4621152e711c06a78f/85450776036.pdfIn PDF document text
    • https://atrax.hr/files/44345774115.pdfIn PDF document text
    • http://parentini.it/userfiles/files/rixigoxapirifotovonago.pdfIn PDF document text
    • http://cameralehiep.com/hinhanh_fckeditor/file/gisepetojezadodisava.pdfIn PDF document text
    • http://www.contectrade.hu/fckfiles/file/38798288410.pdfIn PDF document text
    • http://meteosputnik.ru/userfiles/file/45749097124.pdfIn PDF document text
    • https://renfrewareahealthvillage.ca/ckfinder/userfiles/files/rudagojekoxep.pdfIn PDF document text
    • http://www.pianoszimmermann.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160a91f11032ea---fekowiki.pdfIn PDF document text
    • https://xanbiente.de/userfiles/file/bajorodovefomitodo.pdfIn PDF document text
    • http://avandcie-automation.fr/ckfinder/userfiles/files/3166160036.pdfIn PDF document text
    • https://massagetheory.ca/wp-content/plugins/super-forms/uploads/php/files/7143b68c1f0ae97bc6a5c46900117107/tevojepuramixenup.pdfIn PDF document text
    • http://motoren-adachi.com/js/upload/files/foxarewakenujerixenawug.pdfIn PDF document text
    • http://ahdongjiu.com/upload_fck/file/2021-7-14/20210714054336344019.pdfIn PDF document text
    • http://gramercy-grand.ru/files/file/84779318076.pdfIn PDF document text
    • https://askopenko.com/wp-content/plugins/super-forms/uploads/php/files/93245bb83d6d03a32a963743fab8cc4d/dagaboruvosotozu.pdfIn PDF document text
    • https://bwawarszawa.pl/upload/file/20101924402.pdfIn PDF document text
    • https://asigurareingermania.ro/wp-content/plugins/super-forms/uploads/php/files/tbb8v52ckun0ls0hqgevsaru9o/giridoderud.pdfIn PDF document text
    • http://prodottoitalia.eu/userfiles/files/kilevutogawolupewilopu.pdfIn PDF document text
    • http://cicm2015.mist.ac.bd/app/webroot/ckfinder/userfiles/files/kixuvoxusafi.pdfIn PDF document text
    • https://tootooair.com/FileData/ckfinder/files/20210704_6590034CE1B3F38E.pdfIn PDF document text
    • https://lakecountyoralsurgery.com/wp-content/plugins/formcraft/file-upload/server/content/files/16078d66a8df10---34512538278.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/GLLx1DTH0VQ/uplcv?utm_term=is+shl+test+difficultPDF 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_off0000eeb4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEEB4 16480 bytes
SHA-256: 1bd4712878476661117240aefa3f0a18a4c2a94acba20342c2c586a8362ac8a2
font_01_sfnt_off00011940.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11940 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00013157.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13157 10136 bytes
SHA-256: e16d02041e16c77533e83b27f0d0dfa6d97f95c06ddf54e27b9f1154987818a6