Malicious PDF — malware analysis report

Static analysis result for SHA-256 3c31ec4f701a0769…

MALICIOUS

PDF

85.0 KB Created: 2021-02-18 20:04:23 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-22
MD5: 848c3d37829b438adda0fcc7b06eca47 SHA-1: d022b09f754572a6fd68e1c3d08b3b2f647c25cf SHA-256: 3c31ec4f701a07697a914a338f7f8c357d0808e1b34609a554fecf9a51616d77
186 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. 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-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • Small PDF contains mass external PDF link farm critical PDF_SEO_LINK_FARM
    Small PDF contains many clickable external PDF links, mostly clustered on one host. This matches generated SEO/link-farm PDF carriers used to route users into malicious or unwanted-software delivery chains, rather than a normal document citation pattern.
  • 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://crophysi.ru/123?utm_term=samsung+smartcare+vrt+plus+washer+sc+code PDF link annotation
    • http://grafoanaliz.ru/how_do_you_deal_with_an_emotionally_abusive_mothertoxe6.pdfIn PDF document text
    • http://mjawebdesign.net/4872379638g3uen.pdfIn PDF document text
    • https://cdn.sqhk.co/vofonowul/dihwkhe/71209648393.pdfIn PDF document text
    • http://hhizmet.com/31545381138xb5mz.pdfIn PDF document text
    • https://kofasarafafe.weebly.com/uploads/1/3/5/3/135390193/webolo.pdfIn PDF document text
    • https://fidagavatijib.weebly.com/uploads/1/3/1/3/131398583/mulikoj_vepiz.pdfIn PDF document text
    • https://taburexil.weebly.com/uploads/1/3/4/3/134374137/venobusex-rivuxakuvuzabo-fejuluru-panisunim.pdfIn PDF document text
    • http://twitter-center.com/aiag_s_fmea_manual_4th_edition_free0hv8h.pdfIn PDF document text
    • https://cdn.sqhk.co/tokotuxajif/ejcqEdh/motorola_razr_review_2020.pdfIn PDF document text
    • https://webegerux.weebly.com/uploads/1/3/4/7/134759049/gurofirexulif-xusinaxag.pdfIn PDF document text
    • https://zerimesatevig.weebly.com/uploads/1/3/4/8/134879836/5974949.pdfIn PDF document text
    • https://naweviwezufas.weebly.com/uploads/1/3/1/8/131856142/430b2.pdfIn PDF document text
    • https://cdn.sqhk.co/midipijikami/k8hfCja/telecharger_solitaire_classic_klondike.pdfIn PDF document text
    • https://cdn.sqhk.co/kulobuwaxegu/9kgehhx/dog_runny_nose_lethargy_vomiting.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_off00010892.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10892 5744 bytes
SHA-256: 4a0b8cded71abc85c202c89d26fe21deb0729b631c5f96b26948d22e2473c8fc
font_01_sfnt_off00011c08.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11C08 12328 bytes
SHA-256: 417cfe51b60f72715b96be6ce3c009a07957af97ae127ce0f046d0f4165ed281