Malicious PDF — malware analysis report

Static analysis result for SHA-256 d90ef2f9cc183777…

MALICIOUS

PDF

92.4 KB Created: 2021-05-30 04:18:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-16
MD5: 3e6e167ee9902adbba997b2f2a9980dd SHA-1: f2e14a4d96f5dbb09088e335c00dfc4e43dc8c02 SHA-256: d90ef2f9cc1837779f26b11c3eccb6433660a0dc571e7330974170303bf6808a
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It functions as a link farm, containing numerous URLs pointing to compromised CMS uploads and disposable hosting, suggesting an attempt to distribute or obscure malicious content. The presence of multiple external URIs and a link farm structure points towards a phishing or malware distribution scheme.

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 http://szwygs.com/upload/devin.pdf In PDF document text
    • https://www.finestkindcharter.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608e07e3ace3d---jaxuzubujakosiwisafiwewik.pdfIn PDF document text
    • https://www.accidentinjurylascruces.com/wp-content/plugins/super-forms/uploads/php/files/6e6g8vactbpapmjnp71vqf48q6/xapovog.pdfIn PDF document text
    • http://gymostrov.org/gymostrov/userfiles/file/78793744849.pdfIn PDF document text
    • http://www.catalogodecineargentino.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a527bf5edf6---74254133455.pdfIn PDF document text
    • https://webgirls-studio.com/wp-content/plugins/formcraft/file-upload/server/content/files/16097d3f3ca285---bibuzogenanumurumetunu.pdfIn PDF document text
    • http://skrabl.pl/www/rpbd/fck/file/71710017734.pdfIn PDF document text
    • https://baohohoanglong.com/userfiles/file/wakiwonokipir.pdfIn PDF document text
    • https://segurosjdd.com/wp-content/plugins/super-forms/uploads/php/files/cfu24ohjvgo6cvlk3hngjpks13/mobemefon.pdfIn PDF document text
    • http://mijneigenlift.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1606cc36e1b437---padalapapakixu.pdfIn PDF document text
    • https://nobleanimalsanctuary.org/wp-content/plugins/super-forms/uploads/php/files/tmp/mazowetoregojuwopiguz.pdfIn PDF document text
    • http://www.linkkorea.co.kr/wp-content/plugins/formcraft/file-upload/server/content/files/1607881af0e397---33566814092.pdfIn PDF document text
    • http://www.ponderosafestival.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607f617c9bcf0---83827445692.pdfIn PDF document text
    • http://www.klpreschool.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a46e2e055fd---74905457526.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/zMnd8XtcwSM/uplcv?utm_term=saxon+phonics+kindergarten+worksheetsPDF 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0001296f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1296F 5628 bytes
SHA-256: ddbd2da3ad5797efd2e954f4886f4b01feb351519d237d373b6ecebbe69f6304
font_01_sfnt_off00013ca1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13CA1 11152 bytes
SHA-256: 1ab409d7e0edb78d550fee197c99ad1439121768774bc6aeda684e58292b86f9