Malicious PDF — malware analysis report

Static analysis result for SHA-256 53f42ac43e293ad9…

MALICIOUS

PDF

81.1 KB Created: 2021-06-26 18:41:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-13
MD5: 47130454c37c986ddb48fba01970e0e9 SHA-1: 67f2038e56e1e0a9f66aa5553c7eb5b6110fd8bf SHA-256: 53f42ac43e293ad9588200f9ca39e54cf2976a50174d215e13c8c850f99f3af5
156 Risk Score

Malware Insights

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

The sample is a PDF file detected as malicious by ML classifiers and ClamAV. It functions as a link farm, containing numerous URLs that point to potentially compromised WordPress upload directories. These links likely serve to distribute further malicious content or lead users to phishing sites. The presence of multiple external URIs and link farm heuristics indicates a deliberate attempt to redirect users to malicious infrastructure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

Heuristics 6

  • 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.
  • 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://avenirpourtous.fr/wp-content/plugins/formcraft/file-upload/server/content/files/16079db8817ffd---67231590123.pdf In PDF document text
    • https://formapolis.it/wp-content/plugins/super-forms/uploads/php/files/3f6b6b82f65168c6854dbf114ece445b/xezavidisobenikoveloxokaf.pdfIn PDF document text
    • https://xn-----6kcabagcgfjsxjciriy6alkh6a7aqk.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/dd87de7c4dd524702b3506dd4a3cba4d/bulifanokisutojagej.pdfIn PDF document text
    • http://www.sunarmisir.com.tr/wp-content/plugins/super-forms/uploads/php/files/atltqkoj9iv6u2dpsgqf5crhq2/votivotagakuxuwup.pdfIn PDF document text
    • http://xn--90ad5ackt1d.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/e34e7d558069233745473730030561eb/kusaritesaridaneberoxijo.pdfIn PDF document text
    • https://spherule.org/wp-content/plugins/super-forms/uploads/php/files/61u7ib8h33k6rjf0grl7ek41r7/simininaberubim.pdfIn PDF document text
    • https://www.m2asolutions.com/wp-content/plugins/super-forms/uploads/php/files/15a881695b634184aaa1dc92c1762890/82326995789.pdfIn PDF document text
    • https://drahmetbostanci.com/wp-content/plugins/formcraft/file-upload/server/content/files/160804647c1939---74807664402.pdfIn PDF document text
    • https://estigotours.com/wp-content/plugins/super-forms/uploads/php/files/12a58606cb0a7ad33beea4c5733a9e77/65262750885.pdfIn PDF document text
    • https://www.rockandroll.blog.br/wp-content/plugins/super-forms/uploads/php/files/jp4f5hh77vnaleifg75t1ncok0/verejomevipuvuziradovezi.pdfIn PDF document text
    • http://www.mywil.ch/wp-content/plugins/formcraft/file-upload/server/content/files/160c154fad70e7---rifom.pdfIn PDF document text
    • http://mazurubezpieczenia.pl/zdjecia/fck/file/paxesojabiwosisus.pdfIn PDF document text
    • https://binarbaid.com/public_html/userfiles/file/50757013792.pdfIn PDF document text
    • http://patriabrno.cz/userfiles/files/wezot.pdfIn PDF document text
    • https://www.truegridpaver.com/wp-content/plugins/super-forms/uploads/php/files/af80825bbcb1e1e4dbe78c75dc1a5373/wubebip.pdfIn PDF document text
    • https://agrachoff.ru/wp-content/plugins/super-forms/uploads/php/files/bdcfcb913e4bca22f7a083510f7ebaa0/7161630558.pdfIn PDF document text
    • https://www.gml.de/wp-content/plugins/formcraft/file-upload/server/content/files/1606c914ea4eab---85013465462.pdfIn PDF document text
    • https://gradeagroup.com/wp-content/plugins/super-forms/uploads/php/files/tfsdb9nn3ci7nv0lufuistrf07/vubuwabu.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/16071618913dbe---39802902381.pdfIn PDF document text
    • http://www.consorcio.edu.pe/wp-content/plugins/formcraft/file-upload/server/content/files/1609c25da57950---fitevage.pdfIn PDF document text
    • http://www.maoles.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a4ecb6ed476---rodujulotisogemefan.pdfIn PDF document text
    • https://liniagdanskzydowo.pl/files/vadonafiwowisebigozafozok.pdfIn PDF document text
    • https://snabavto.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607eb717be46f---12899295004.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3vuEKuznOb8/uplcv?utm_term=happy+marriage+anniversary+di+and+jiju+quotesPDF 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_off0000d9cb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD9CB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f1dd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF1DD 16116 bytes
SHA-256: 21548f46469789d2cc91f59de6d4c12f5963e0056b5f17d7a35b45fc13be6233
font_02_sfnt_off00011b4e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11B4E 11236 bytes
SHA-256: 3af621270bc198532a2d73b2ceeba22a1431a2126cfc314f5164532e0a524068