Malicious PDF — malware analysis report

Static analysis result for SHA-256 7cd527f20ab1abab…

MALICIOUS

PDF

70.9 KB Created: 2021-06-14 21:01:02 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-23
MD5: 1e23ccaf801f0cff7b5dcba4ab0544d0 SHA-1: 96c6ccc4dcc7aaf8c9570b290669f4c2b9660471 SHA-256: 7cd527f20ab1ababd8abad13923d7623392ed260bea8da1a629a1b36215f4bd3
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript T1203 Exploitation for Client Execution

The PDF file contains numerous links to compromised WordPress sites and disposable hosting, suggesting a link farm designed to redirect users to malicious content. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and embedded URLs point towards exploitation of PDF vulnerabilities or social engineering to lead users to external malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://oniceh.ru/uplcv?utm_term=answer+smash+questions+and+answers PDF link annotation
    • http://www.expertnutritionadvisor.com/wp-content/plugins/formcraft/file-upload/server/content/files/160898d05aba8c---11384057772.pdfIn PDF document text
    • http://wakingbeauty.com/wp-content/plugins/formcraft/file-upload/server/content/files/160858ee8081dd---zonugexigozepijitikowam.pdfIn PDF document text
    • http://www.opencalgary.org/wp-content/plugins/formcraft/file-upload/server/content/files/160c45b80241e6---48242442310.pdfIn PDF document text
    • http://www.awakohchang.com/image/upload/File/ejogevaz.pdfIn PDF document text
    • http://abwlanham.com/uploads/files/83368455653.pdfIn PDF document text
    • http://cokhitienvuong.com/uploads/files/subezewugoxaperapot.pdfIn PDF document text
    • http://apexnepaltravel.com/userfiles/file/vamuwinotis.pdfIn PDF document text
    • https://leesman.com/wp-content/plugins/super-forms/uploads/php/files/dde7a7802c4ef3d9ccbc8cf534920f34/kurogifuwinofekoxegavip.pdfIn PDF document text
    • http://kraljicabih.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b25471847dc---70061088373.pdfIn PDF document text
    • https://backcountryplayground.com/wp-content/plugins/super-forms/uploads/php/files/5c29bb79b37ff062bcb48991fc6c9550/25866438411.pdfIn PDF document text
    • https://agsposure.org/wp-content/plugins/super-forms/uploads/php/files/8733f356b516e5afcf1176b7b0aedaf2/kuzadugojotobakumopigowir.pdfIn PDF document text
    • http://neonatal-surgery.ru/userfiles/files/vejobufafugo.pdfIn PDF document text
    • https://postscriptproductions.com/wp-content/plugins/formcraft/file-upload/server/content/files/16098f7cd93a7a---94825448710.pdfIn PDF document text
    • http://wypelnienia.kratex.pl/wp-content/plugins/super-forms/uploads/php/files/2e223c6b616f2fbb41fc05b086666815/sagiposajodup.pdfIn PDF document text
    • http://seoulsquare.com/userfiles/file/mabuxoreredepaladokabop.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_off0000d8f1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD8F1 5240 bytes
SHA-256: 4682708b65b61828aa17809cf304acb65599a15ccf95b5ff42e5df244f33d677
font_01_sfnt_off0000ea9d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEA9D 10120 bytes
SHA-256: 920d0c4d31dc9e516e83adb84586346f0ff8377901939303e83d4884c540b832