Malicious PDF — malware analysis report

Static analysis result for SHA-256 440146df835da784…

MALICIOUS

PDF

74.1 KB Created: 2021-09-20 07:15:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 955a11e826369e0d3a8ac4621747e4d1 SHA-1: 9d475d3e41539068660f5a175ad4a33dc4239d18 SHA-256: 440146df835da784b4356c107d3c99c1a933e16f9595ab629e575a24ecee0734
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF containing embedded JavaScript, which is a common technique for delivering malicious content. The PDF also contains numerous external URIs, many of which point to compromised websites or link farms, suggesting an attempt to redirect users to malicious sites. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9971

Heuristics 7

  • 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.
  • 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://medvor.ru/uplcv?utm_term=arc+measure+with+equations PDF link annotation
    • http://aibasavar.edu.bd/app/webroot/ckfinder/userfiles/files/fudaxexise.pdfIn PDF document text
    • https://makanbanyak.net/contents/files/vidijuzajeroz.pdfIn PDF document text
    • https://pnp-studio.com/fckeditorfiles/file/retakuvilovuwanozimod.pdfIn PDF document text
    • http://waterlootour.com/FileData/ckfinder/files/20210917_E8A69E45DBBA8C6F.pdfIn PDF document text
    • http://nissanotogovap.com/uploads/images/files/54539448542.pdfIn PDF document text
    • http://sys-svinding.dk/userfiles/file/6560707216.pdfIn PDF document text
    • http://srilakshmienterprises.net/uploads/26190450290.pdfIn PDF document text
    • http://www.tenniscanberra.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1613e149e3ec3c---nexuked.pdfIn PDF document text
    • https://cosmopolitanhotel.eu/uploads/wysiwyg/files/65922538623.pdfIn PDF document text
    • http://poptheme.cn/uploadfile/files/20210909_083049.pdfIn PDF document text
    • http://ecole.ru/text/images/file/lidasobuwupesadegofoputo.pdfIn PDF document text
    • http://s8radziejowice-paszkow.pl/userfiles/file/ladozo.pdfIn PDF document text
    • https://ppkh.net/userfiles/file/jodinimetopakob.pdfIn PDF document text
    • http://rama-sp.com/rama/webroot/js/ckfinder/userfiles/files/7962842795.pdfIn PDF document text
    • https://magazinul-de-instalatii-sanitare.ro/app/webroot/files/userfiles/files/temisedidituxesekakokoj.pdfIn PDF document text
    • https://andhimazhai.com/images/files/dovegesepezowe.pdfIn PDF document text
    • http://dragoniresorts.com/userfiles/buvijoj.pdfIn PDF document text
    • http://podarox.ru/public/files/81220061220.pdfIn PDF document text
    • http://stroynerud-sm.ru/wp-content/plugins/formcraft/file-upload/server/content/files/161392738839b5---83398364049.pdfIn PDF document text
    • http://pospatrans.cz/UserFiles/File/68829156107.pdfIn PDF document text
    • https://www.ferienhof-schneider.de/wp-content/plugins/formcraft/file-upload/server/content/files/161381098ec4da---7244890163.pdfIn PDF document text
    • 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_off0000bde3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBDE3 10760 bytes
SHA-256: 4fe27d2ce4daccb047cc378166831ef57d4951d731ce75344e0877e07694cfa5
font_01_sfnt_off0000d691.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD691 17388 bytes
SHA-256: c0436bab57504591bbd26c6833389b32d5efbdc9b30382041e03b99582ad5156
font_02_sfnt_off00010320.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10320 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1