Malicious PDF — malware analysis report

Static analysis result for SHA-256 66d4f49d2a1a6075…

MALICIOUS

PDF

141.7 KB Created: 2021-07-16 11:55:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: bbfcf26ffae7e42a5e58ef8f662df4ec SHA-1: f0bcf183bb1ff2d1b08f9d0b05df36b73a493cb3 SHA-256: 66d4f49d2a1a60758bc1dfd3eb3b063d3b497c751561cbf4f8df026909c4a612
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file contains a link farm, with numerous URLs pointing to compromised WordPress sites and other disposable hosting. The ML classifier strongly indicated maliciousness, and the heuristics confirm the presence of multiple links to compromised CMS uploads and SEO-focused link farms. The document body is heavily obfuscated and unreadable, suggesting it serves primarily as a container for these malicious links rather than user-facing content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9802

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 http://leasingtowers.com/ckfinder/userfiles/files/xenisogiguwatetesag.pdf
    • http://myboydfamily.com/clients/7/7f/7f513a2250c12de81a70a6735749c289/File/weruminilomoboxofodupu.pdf
    • https://takiminsahada.com/wp-content/plugins/super-forms/uploads/php/files/l1ridd8kjqmr67o4knmebums7v/43851014319.pdf
    • https://olterus.com/contents//files/11626866327.pdf
    • https://www.businesswatchguardingservices.co.uk/wp-content/plugins/super-forms/uploads/php/files/b3hdl6aknecqlavf5s7pii67ta/69955899252.pdf
    • https://beatmuellerfoto.ch/userfiles/files/falomurexemokogoxewi.pdf
    • https://www.cdscabling.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16072f36dd8484---laguzirotosuzuxanamuga.pdf
    • https://www.jahnigterbraak.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160a004065f436---lubowikaxolig.pdf
    • http://mytmbc.org/fckimage/file/43030611555.pdf
    • https://kemxoi.vn/app/webroot/files/images/pages/files/34472770321.pdf
    • http://centrlita.ru/archive/image/file/zataxugopisabagofixalage.pdf
    • https://stakeoutllc.com/wp-content/plugins/super-forms/uploads/php/files/27f408043e9ccd7707d350f7b922086e/48190587995.pdf
    • http://pomocnaukowa.net/Upload/file/30156896570.pdf
    • https://autosofortkauf.ch/wp-content/plugins/super-forms/uploads/php/files/f6gh1dt4h8nm8h7n9a2t250bu3/98657436288.pdf
    • http://jungvassar.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/wixugafoluvebemakune.pdf
    • https://adepotcustom.com/UploadFiles/file/20210621104138176.pdf
    • https://riondene.ch/img/uploads/file/siduralakuja.pdf
    • https://ekselantechnology.solutions/ckfinder/userfiles/files/zuliw.pdf
    • http://chocoenglish.com/_UploadFile/Images/file/rakunapofetezitupuvonazox.pdf
    • https://zweefvlieg.net/userfiles/file/81528737572.pdf
    • http://www.petersmetalstitching.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1608d2ef8dad83---rawutuf.pdf
    • http://alfavs.eu/userfiles/file/gaxix.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/ngfLrbzwjls/uplcv?utm_term=neville+brody+the+face
    • 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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f369.bin
74ac11c163e8255eacb31945755fb90ad910605b74e320df3e6ac535c85db3ce
pdf-font-stream PDF embedded font (sfnt) at offset 0xF369 16940 bytes
font_01_sfnt_off00011f63.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x11F63 16792 bytes
font_02_sfnt_off00013771.bin
afbb198694baa0cfe63d0c02598fb507932cefba65d62743a6fa8ba2124b6c49
pdf-font-stream PDF embedded font (sfnt) at offset 0x13771 85124 bytes
font_03_sfnt_off00020ea1.bin
49d679c6f6ddab0d5af4221590a69c0f3b4f0ebeaf4ef64c555f7535ac4d40a4
pdf-font-stream PDF embedded font (sfnt) at offset 0x20EA1 10596 bytes