Malicious PDF — malware analysis report

Static analysis result for SHA-256 39977c809b5126f6…

MALICIOUS

PDF

77.1 KB Created: 2021-09-08 16:10:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 7bb25b92e52afb8d0c8fd7e4e72277ac SHA-1: bdb229e46913a858d06dfd51e7b45ef83818e064 SHA-256: 39977c809b5126f6d599b88d37f6ed496ac9771864d85c169bb07d8456fe6609
104 Risk Score

Malware Insights

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

The PDF contains an embedded JavaScript stream and multiple external URIs, many of which point to compromised WordPress sites acting as a link farm. The ML classifier strongly indicates maliciousness, and the presence of a link farm suggests an attempt to redirect users to malicious or phishing content. The embedded JavaScript likely facilitates this redirection or further malicious activity.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9943

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 http://leap-egypt.com/wp-content/plugins/formcraft/file-upload/server/content/files/16133c6c046118---rutadej.pdf In PDF document text
    • https://mtmnetwork.net/uploadEditor/files/puniboxikodadivawut.pdfIn PDF document text
    • https://seeandhearbetter.ie/img/shop/contents/35922604078.pdfIn PDF document text
    • http://paddockj.com/user_data/editor/ckfinder/core/connector/php/upload/files/pagevarizazafa.pdfIn PDF document text
    • https://www.actionconstructionjax.com/wp-content/plugins/super-forms/uploads/php/files/509b4df56ca2caa7d0bd4c4074eedc00/3368378510.pdfIn PDF document text
    • http://flixgolf.com/ckeditor/ckfinder/userfiles/files/28832702684.pdfIn PDF document text
    • http://wwm-quanta.com/upload/files/5709569845.pdfIn PDF document text
    • https://sayurhijau.com/contents/files/wumorikomuvuvu.pdfIn PDF document text
    • http://actinq.nl/upload/file/risavo.pdfIn PDF document text
    • http://teakdeck.pl/files/file/pawozalalo.pdfIn PDF document text
    • http://pneusmarene.it/images/file/kovidikipet.pdfIn PDF document text
    • https://brylka-kfz.de/wp-content/plugins/formcraft/file-upload/server/content/files/1613227684cb84---fotibixodix.pdfIn PDF document text
    • http://autosoftware.company/autoresponders_images/files/kabogur.pdfIn PDF document text
    • http://themadthinker.com/temp/vinney/HTML/userfiles/file/1333353898.pdfIn PDF document text
    • http://donauwell.at/userfiles/file/5266249999.pdfIn PDF document text
    • http://zhengfutz.com/v15/Upload/file/202196830211036.pdfIn PDF document text
    • http://culbertsonlawyer.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/23878250298.pdfIn PDF document text
    • http://idolyokocho.com/js/ckfinder/userfiles/files/nalanewi.pdfIn PDF document text
    • http://vongtaygiay.net/media/ftp/file/34648274889.pdfIn PDF document text
    • http://ruben.pl/ckfinder/userfiles/files/62906651215.pdfIn PDF document text
    • http://35ju.21tg.cn/uploadfile/ckeditor/files/63814335564.pdfIn PDF document text
    • https://webmakler.org/userfiles/file/77542007282.pdfIn PDF document text
    • http://gocchame.vn/app/webroot/img/uploads/files/museresusuru.pdfIn PDF document text
    • https://gamedunyasi.com/calisma2/files/uploads/jusudibovog.pdfIn PDF document text
    • http://alpes-maritimes.proximeo.com/ckfinder/userfiles/files/tinebam.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/cv9VXjIrmdE/uplcv?utm_term=jasper+jones+kate+mulvany+pdfPDF 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_off0000c7a4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC7A4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000dfb6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDFB6 17552 bytes
SHA-256: 2a98d5f8db6e0c29302528af3a56fdf5691ea251e1508f3727e37b0489b3dd42
font_02_sfnt_off00010d1a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10D1A 11060 bytes
SHA-256: 186e4e3cee836e204edd1d0412f0e929cde3e3515e1330e905261e1fd12a9f1b