Malicious PDF — malware analysis report

Static analysis result for SHA-256 c7b8b20b0fe78964…

MALICIOUS

PDF

97.0 KB Created: 2021-04-09 11:50:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-08-20
MD5: cf321c5846c74685dbc13bf96177508d SHA-1: 2112b77950117321b53f613419acc62b830ed16c SHA-256: c7b8b20b0fe789646dccfd65eb4f9e039310e54d2a8d691c645c60f9d5ac2b45
186 Risk Score

Malware Insights

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

This PDF file was identified as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains a large number of external links, many pointing to disposable hosting, suggesting it functions as a link farm. The primary URL, https://golowaki.ru/strik?utm_term=maus+tank+images, is likely part of a phishing or scam campaign. No scripts were extracted, but the structure and URL distribution strongly suggest a malicious document designed to redirect users to potentially harmful sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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://golowaki.ru/strik?utm_term=maus+tank+images PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4490752/normal_6040a86687586.pdfIn PDF document text
    • https://fujikoxeloto.weebly.com/uploads/1/3/5/3/135307408/f9ce0df64.pdfIn PDF document text
    • http://vizit.store/bizegenezisonisec299p.pdfIn PDF document text
    • https://turetajonu.weebly.com/uploads/1/3/4/6/134629909/43078478a0360.pdfIn PDF document text
    • http://gapofar.22web.org/antonyms_worksheet_for_grade_2.pdfIn PDF document text
    • http://snail-case.store/mujasokuxogawazujutosikfqt4y.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4460690/normal_6042a96a66b9b.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4365607/normal_6050d8b4af7da.pdfIn PDF document text
    • http://sellforce.ru/53576386407n9n23.pdfIn PDF document text
    • http://tersq.space/nemesis_safety_glasses_for_sale_near_meimfuu.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4365549/normal_605a739e2a327.pdfIn PDF document text
    • http://xazusifiwo.iblogger.org/67172629584.pdfIn PDF document text
    • https://mobisikude.weebly.com/uploads/1/3/1/6/131606420/2f04b64.pdfIn PDF document text
    • http://psychologyrelax.xyz/xanorata9ohve.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4478402/normal_606bf526d6b7d.pdfIn PDF document text
    • http://xuxuxib.iblogger.org/gipewotufegoza.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://8dfd47f4-e591-4377-92a3-bdbf91d41e5a.filesusr.com/ugd/a58b01_cff70bab91f14bf8a3b65b75ceb45ce1.pdf?index=trueIn PDF document text
    • https://3633ae4e-9acc-45df-885e-1bfa1481cb44.filesusr.com/ugd/e73054_87f376659d924fef991fa0060662571d.pdf?index=trueIn PDF document text
    • https://ba85394b-11ac-4ca4-926b-74ca936c52e1.filesusr.com/ugd/5ccfc8_53545dfefd344423929e25ee9fdc35b1.pdf?index=trueIn PDF document text
    • https://eaa62ee9-779c-4a2d-9f50-6c66b019a99c.filesusr.com/ugd/1cc777_9cf089909e124a85b4ff6e4b36783073.pdf?index=trueIn PDF document text
    • https://de99c131-68bf-4271-bcef-cda292486844.filesusr.com/ugd/f5892c_eee919a68f2443c78392b8c1233e25b4.pdf?index=trueIn 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_off00013f6b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13F6B 4944 bytes
SHA-256: 7e30c0e265a73437a151b02d7b5dc0c6c2f7d5e5f8b4d9d322c357b0771cd093
font_01_sfnt_off00015040.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15040 11348 bytes
SHA-256: 0b2e156a65dfcb4f6841cf15436064ee57c807f4de69d37825d6506f4d8246d7