Malicious PDF — malware analysis report

Static analysis result for SHA-256 4cd65091e7a3972f…

MALICIOUS

PDF

78.3 KB Created: 2021-06-15 11:09:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-23
MD5: daa09d888968aaee71d41100c1ea64e8 SHA-1: dd7f52e25cd54325aecf21e5071ad21415d414da SHA-256: 4cd65091e7a3972f3ef2435ca0572b79d580f00768626b1db5bddedf0126dc9b
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It functions as a link farm, with numerous embedded URLs pointing to compromised WordPress sites, suggesting a phishing or malware distribution scheme. The presence of multiple distinct hosts and the use of 'utm_term' parameters in some URLs further support this assessment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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://oniceh.ru/uplcv?utm_term=addition+and+subtraction+word+problems+4th+grade+pdf PDF link annotation
    • https://hps-gruppe.com/wp-content/plugins/super-forms/uploads/php/files/hk7mb7nkc50ne5l2bbrkqnvj5c/64824540240.pdfIn PDF document text
    • http://thm-holding.ru/wp-content/plugins/super-forms/uploads/php/files/80296cc9a0e30b773e2ac7293955e8e4/14427137607.pdfIn PDF document text
    • https://www.modianodesign.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c8585032992---65907129193.pdfIn PDF document text
    • https://hoffmanowska.pl/wp-content/plugins/formcraft/file-upload/server/content/files/16081212b0ea23---vuduxeted.pdfIn PDF document text
    • https://medgarlci.com/wp-content/plugins/super-forms/uploads/php/files/d10c0afd548a230ca969b9aadc6c75b5/96067368886.pdfIn PDF document text
    • http://www.kocay.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/1608c0ece4e063---48133169369.pdfIn PDF document text
    • https://www.synergyheart2heart.team/wp-content/plugins/super-forms/uploads/php/files/sm3euh61qdiidugq1punhch6jd/97567290685.pdfIn PDF document text
    • https://na-nule.ru/wp-content/plugins/super-forms/uploads/php/files/3au6p0lv3budv9hrrktqrt8rv1/45101057320.pdfIn PDF document text
    • https://premiumvipbusiness.com/wp-content/plugins/super-forms/uploads/php/files/3d4b279362152b5333c6190b12a88cef/35178043577.pdfIn PDF document text
    • http://videoacceso.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a8a04b1578a---47399661081.pdfIn PDF document text
    • http://www.a-fairys-choice.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a62f894152e---dotogilonone.pdfIn PDF document text
    • https://gift-edu.ru/wp-content/plugins/super-forms/uploads/php/files/df88028feed74a275451549770398ed2/89680305353.pdfIn PDF document text
    • http://sashtraayurveda.com/ckfinder/userfiles/files/23633638461.pdfIn PDF document text
    • http://apartmaji-zunicmile.com/uporabnik/file/junuv.pdfIn PDF document text
    • https://www.herewardcarpets.co.uk/wp-content/plugins/super-forms/uploads/php/files/494erhs4smgevdng8l1g05j0bp/51983848374.pdfIn PDF document text
    • http://vmkmsz.hu/userfiles/file/93634742720.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_off0000f278.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF278 5880 bytes
SHA-256: 6f768e9f1ffcab18a82067310c4eb6a65794088773bc5a53a8f6c9d7d15a15f7
font_01_sfnt_off00010665.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10665 10940 bytes
SHA-256: ed9b6125af9bfa146648f600a2ee4c29ceb29fc361ba50d744461cfa21760bc6