Malicious PDF — malware analysis report

Static analysis result for SHA-256 13defebbc9fc7fff…

MALICIOUS

PDF

73.0 KB Created: 2021-06-13 13:32:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-23
MD5: 9775f94281cf844e76ffa2c79efca001 SHA-1: 14e812ea346ae5ee224c42eea7aa0a1552e2256c SHA-256: 13defebbc9fc7fffe280398298a6327ef9195046797234e888113b202d2b3d57
156 Risk Score

Malware Insights

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

This PDF file is identified as malicious by ClamAV and an ML classifier, indicating a high probability of malicious intent. It functions as a link farm, directing users to various compromised WordPress sites and potentially disposable hosting domains, likely to distribute further payloads or engage in phishing. The presence of multiple external URIs and the 'PDF_SEO_DISPOSABLE_LINK_FARM' heuristic suggest an attempt to exploit search engine optimization for malicious distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://smidgel.ru/uplcv?utm_term=summertime+saga+guide+pdf+free+download PDF link annotation
    • https://primax.fr/wp-content/plugins/super-forms/uploads/php/files/o3bgp7kmb7g1pl8n5hots4uf30/soxekurolabixojezitilezu.pdfIn PDF document text
    • https://extremetour74.ru/wp-content/plugins/super-forms/uploads/php/files/ff56a72839e1ff4d02861bbad4731b24/zusigifew.pdfIn PDF document text
    • http://muzeumostrowiec.pl/obrazy/file/lufukeginikesibupexirajos.pdfIn PDF document text
    • http://www.champcaregivers.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b4b169c8eb7---poragufow.pdfIn PDF document text
    • https://noukos.gr/wp-content/plugins/formcraft/file-upload/server/content/files/16085f5b96ad24---pijitigelep.pdfIn PDF document text
    • http://www.onegelha.com/wp-content/plugins/super-forms/uploads/php/files/961d1b92c7650ea6dfe21df5bf66114e/luwov.pdfIn PDF document text
    • http://classofjoy.com/KK/userfiles/files/dozerizedifevenawikenoju.pdfIn PDF document text
    • http://www.majorisinvestimentos.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1608414dddd1c8---gulewirebebatuzotuvovag.pdfIn PDF document text
    • http://automsystem.com/UploadFile/file/20210504114754642.pdfIn PDF document text
    • https://janeunchained.com/wp-content/plugins/super-forms/uploads/php/files/5cm44ssif0qq03kloqd1gdu1si/pejomegewomu.pdfIn PDF document text
    • http://pck.malopolska.pl/wp-content/plugins/super-forms/uploads/php/files/c6d40ec055897d48b92dc33a7a299384/vitoxaxuxesefizasema.pdfIn PDF document text
    • http://osullivanspressurewashing.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609ec55502752---47513641828.pdfIn PDF document text
    • https://www.accidentinjuryalbuquerque.com/wp-content/plugins/super-forms/uploads/php/files/bkhekj7etf0o6ekr7b6j906ovr/pufozixapidus.pdfIn PDF document text
    • https://www.energetisch-therapeut-estie.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16089b82935ae7---jabul.pdfIn PDF document text
    • https://psychotherapie-dr-albrecht.de/wp-content/plugins/formcraft/file-upload/server/content/files/1609a5d8aaf77d---sujusumozatuvol.pdfIn PDF document text
    • http://infrabud.eu/fckpliki/file/82532549056.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000de01.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDE01 5556 bytes
SHA-256: 32cf4328e973d0bda275f3b2159850d198cae0a74e946694f1d2304196658dde
font_01_sfnt_off0000f0df.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF0DF 11260 bytes
SHA-256: 5df9845f8739a186a156dfc77428f9ac919bd68e1fdc1aaf4d0c756b56a1a8e3