Malicious PDF — malware analysis report

Static analysis result for SHA-256 c1b8b5ec5a21e63d…

MALICIOUS

PDF

77.9 KB Created: 2021-06-10 13:10:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-23
MD5: 48629973e4b598ae09949a1d65276c90 SHA-1: 8326b1097994eac3da9c010f20d4dc1d44166953 SHA-256: c1b8b5ec5a21e63d30b52f722f10042ddf52966c16150c811bb880399d39fb6b
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was flagged by multiple heuristics and a machine learning classifier as malicious, with ClamAV identifying it as a phishing trojan. The document contains a large number of embedded URLs, many of which point to compromised WordPress sites, suggesting a link farm designed to redirect users to malicious or phishing content. No scripts were extracted from this sample, but the extensive use of external links indicates a social engineering attempt to trick users into navigating to potentially harmful destinations.

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://chcial.ru/uplcv?utm_term=teacher+comments+for+writing PDF link annotation
    • http://uat.ideadunes.com/projects/ideadunes-portfolio-site/wp-content/plugins/formcraft/file-upload/server/content/files/160aed18f556f9---konosobodev.pdfIn PDF document text
    • https://fjordancv.info/wp-content/plugins/super-forms/uploads/php/files/ab7af941c22afcc2b7cd3d6e1bb6be38/paxanitovovekudapa.pdfIn PDF document text
    • http://recamonde.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1606ea2d8a7d05---gizuxudalezazoz.pdfIn PDF document text
    • http://akcjonariusz.com/UserFiles/file/60867908585.pdfIn PDF document text
    • https://adsbudget.net/userfiles/file/motigilisimo.pdfIn PDF document text
    • https://dtcprojects.com.au/wp-content/plugins/super-forms/uploads/php/files/13oknfpk2cpmgmupqk5q6haoht/70402266580.pdfIn PDF document text
    • https://estigotours.com/wp-content/plugins/super-forms/uploads/php/files/8ce99f444dcdc0f6bddfc7d3a59e7228/domogavafukiwemuxodin.pdfIn PDF document text
    • http://herodumpsterrental.com/wp-content/plugins/super-forms/uploads/php/files/c0cde416f6a21a48d2bdebe0cc364715/66776569529.pdfIn PDF document text
    • https://ka-base.no/images_content/file/81148007539.pdfIn PDF document text
    • https://harpethvalleyhealth.com/wp-content/plugins/super-forms/uploads/php/files/ba85b1ab00c6ed12da255acaccf2adad/99165498551.pdfIn PDF document text
    • http://www.jesuseslaroca.org/wp-content/plugins/formcraft/file-upload/server/content/files/160a68bff0a4fd---13777860304.pdfIn PDF document text
    • https://phase1acoustics.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c0aa379ff88---95570208181.pdfIn PDF document text
    • http://countrysquirefoods.com/wp-content/plugins/formcraft/file-upload/server/content/files/16080c76bd8719---384888964.pdfIn PDF document text
    • http://khiconghoixuancong.com/Khicong/admin/userfiles/file/xisoxi.pdfIn PDF document text
    • https://signaturetowerpune.com/wp-content/plugins/super-forms/uploads/php/files/rc6j02fe10f1pisqicu7487f64/jugosagitetog.pdfIn PDF document text
    • https://www.analfissur.com/wp-content/plugins/formcraft/file-upload/server/content/files/16072e31dd118b---tobovulisib.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_off0000f2d6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF2D6 5304 bytes
SHA-256: 2968aba651d625d079e469fb828af803a809025a41c52bc4a20229ec689cace2
font_01_sfnt_off000104ca.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x104CA 10724 bytes
SHA-256: 4d7002170992a502c3763a19b965076521863f9e67b9e6a36f2f4c8c1f242a4a