Malicious PDF — malware analysis report

Static analysis result for SHA-256 53cf7275ea319c5a…

MALICIOUS

PDF

110.2 KB Created: 2021-06-16 08:36:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-01
MD5: 094a593075cc3acc87dcab0a7d38ec34 SHA-1: 244ccd8f46cf3b23e47509ffc5360c1d1f74c03f SHA-256: 53cf7275ea319c5a10511fd59f94d799de64a07b9577493192ce2fb0d5f13bd6
156 Risk Score

Malware Insights

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

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories. Specific URLs and indicators for this sample are listed in the indicators section.

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://wastran.ru/uplcv?utm_term=microeconomics+2nd+edition+goolsbee+pdf PDF link annotation
    • http://cargo3030.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1607343a30af04---86238248480.pdfIn PDF document text
    • https://mikepromedia.com/wp-content/plugins/super-forms/uploads/php/files/goq8g6nfj441mv8986rvhfka67/4341769855.pdfIn PDF document text
    • https://humantouchtranslations.com/wp-content/plugins/formcraft/file-upload/server/content/files/1/1607da1e13c308---ligunuzizewef.pdfIn PDF document text
    • http://www.psstrecno.sk/wp-content/plugins/formcraft/file-upload/server/content/files/160ad6a6e1a6b2---81374407897.pdfIn PDF document text
    • http://english-island.pl/wp-content/plugins/super-forms/uploads/php/files/1i1mgrfurf819q2vs7fpm6ccs5/wefasapuwokejutup.pdfIn PDF document text
    • https://www.scanworld.se/wp-content/plugins/formcraft/file-upload/server/content/files/160b47b2949f3d---bumagojugen.pdfIn PDF document text
    • https://event-connections.net/wp-content/plugins/formcraft/file-upload/server/content/files/160942929b3a04---40496707475.pdfIn PDF document text
    • http://assessmentinsight.com/ckfinder/userfiles/files/vewixiguwa.pdfIn PDF document text
    • https://grahampropertytax.com/wp-content/plugins/super-forms/uploads/php/files/b2cb895934bacbee37c30d7ab38ebb2d/20158554284.pdfIn PDF document text
    • https://www.kngroup.com/wp-content/plugins/formcraft/file-upload/server/content/files/160963f7254078---86847952219.pdfIn PDF document text
    • https://aimara-bg.com/userfiles/file/penalajij.pdfIn PDF document text
    • http://aeskulap24h.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609f5db110dbc---40547934873.pdfIn PDF document text
    • https://soudurelausiere.ca/upload/editor/file/sejaga.pdfIn PDF document text
    • http://asirius.su/wp-content/plugins/super-forms/uploads/php/files/539f6722e736c808fcea3fa863e8a19c/3369294023.pdfIn PDF document text
    • https://www.uniqueartzz.com/wp-content/plugins/super-forms/uploads/php/files/qsce1tto83n457ot06r6pfinr2/22578344678.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_off00016e15.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x16E15 5540 bytes
SHA-256: dbe0fb215e0481c34b3d51613aec341d16b5805d0492c2e444c0103f9fb69f4d
font_01_sfnt_off000180e5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x180E5 12648 bytes
SHA-256: c4cbe059e8b2a235e1fa2e9f8d46558fc013004fd43a161c6518a54579274754