Malicious PDF — malware analysis report

Static analysis result for SHA-256 07b433c8a787b62e…

MALICIOUS

PDF

84.7 KB Created: 2021-09-17 07:50:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 21dd68fa98b154bd3be65f3a4aec8171 SHA-1: 2e771f97b94f0afbd19ebc7d4ab8623db9ecd2c3 SHA-256: 07b433c8a787b62e2b27b6d63e38e21ee77f4ef63711e84b3a14c49953bda663
96 Risk Score

Malware Insights

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

The PDF contains a large number of embedded URLs, many of which point to compromised WordPress sites and other disposable hosting. The ML classifier strongly indicated maliciousness, and the structure suggests a link farm designed to manipulate search engine results or redirect users to potentially harmful content. No scripts were extracted, limiting the analysis of direct execution vectors.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9912

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://kaztelcom.kz/ckfinder/userfiles/files/lutufowejukis.pdf In PDF document text
    • https://gotoko.com/cmsv2/upload/files/wusufawexu.pdfIn PDF document text
    • http://ng-sons.com/userfiles/file/13975653732.pdfIn PDF document text
    • https://estoniapools.com/contents/files/81224995756.pdfIn PDF document text
    • https://robertmatzuzi-massagetherapist.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16138e8a33c320---mamir.pdfIn PDF document text
    • http://www.a-fairys-choice.com/wp-content/plugins/formcraft/file-upload/server/content/files/16130a8333d550---89605498219.pdfIn PDF document text
    • http://varadimasszazs.hu/uploads/files/95832843872.pdfIn PDF document text
    • http://www.bridalchapel.com/wp-content/plugins/formcraft/file-upload/server/content/files/161401ed558774---ligugirelezobiluvipuwu.pdfIn PDF document text
    • https://maintogelonline.bet/contents/files/taxamos.pdfIn PDF document text
    • http://mulroyenvironmental.ie/userfiles/file/89799579015.pdfIn PDF document text
    • https://tranhtreo.com/images/ckeditor/files/61362115507.pdfIn PDF document text
    • http://cuacuongiare.vn/upload/files/libemodunonepejo.pdfIn PDF document text
    • http://keystoparadise.com/userfiles/files/degasopunonenavajini.pdfIn PDF document text
    • https://gz-topstar.com/wp-content/plugins/super-forms/uploads/php/files/df5743b6536879e58e362a995d61f196/bukosupulomovepul.pdfIn PDF document text
    • http://sb-78.ru/files/file/lapepodijedozurinanimo.pdfIn PDF document text
    • https://sodigital.it/wp-content/plugins/formcraft/file-upload/server/content/files/16138dc8b6d0a8---wexizar.pdfIn PDF document text
    • http://xn--80ackbssfuieecff0e8c.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/urlcl3ll3llni3ai8q7n6qj6r5/witisorezikosalur.pdfIn PDF document text
    • https://egyediajandekotletek.hu/mvc/userfiles/file/vamizipomabezaba.pdfIn PDF document text
    • http://geotersrl.it/file/nasonazuxeridepotumi.pdfIn PDF document text
    • http://thewellmanteam.com/userfiles/files/vesovepowo.pdfIn PDF document text
    • http://commsoft.nu/demo/ktb/wsmbilder/files/26707258828.pdfIn PDF document text
    • https://sibois.eu/userfiles/file/suwovabagile.pdfIn PDF document text
    • http://www.keizerco.nl/userFiles/file/pusefara.pdfIn PDF document text
    • http://qamsar.org/userfiles/files/mikiguwabigu.pdfIn PDF document text
    • http://knowleangling.co.uk/ckfinder/userfiles/files/1499596373.pdfIn PDF document text
    • http://aptekarynek.pl/zdjecia/fck/file/59606528434.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BvfzZFkJO3s/uplcv?utm_term=how+to+convert+video+in+audioPDF 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_off0000e4b8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE4B8 10392 bytes
SHA-256: 29d915d901052055aa3c188cd70073007c3581df5704c915dc3e0cb214ded930
font_01_sfnt_off0000fc56.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFC56 18404 bytes
SHA-256: b97eaa2e7d9b7e33261625633ece009821a2e9f409beb41bc88342a35c848c9d
font_02_sfnt_off00012c96.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12C96 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1