Malicious PDF — malware analysis report

Static analysis result for SHA-256 661b902d9fa31494…

MALICIOUS

PDF

76.0 KB Created: 2021-04-08 00:22:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-23
MD5: 36fc755491b5d58937453cd1de533d21 SHA-1: b9ed4bcb83a0fef93e4ae037847becd223a0a916 SHA-256: 661b902d9fa31494cbf719e91309778ab06f5af35f511cadad7ad4585289d85c
186 Risk Score

Malware Insights

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

This PDF file was identified as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains a large number of external links, many hosted on disposable domains, suggesting a link farm or SEO spam operation. The presence of external URIs and a link farm heuristic points towards an attempt to redirect users to potentially malicious or unwanted content. No scripts were extracted, but the PDF structure itself is used to host numerous external links.

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
  • 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://druttle.ru/strik?utm_term=pride+and+prejudice+best+quotes+with+page+numbers PDF link annotation
    • http://demask.space/philippine_folk_dance_steps2d9vr.pdfIn PDF document text
    • http://tegubija.mypressonline.com/catalogo_avon_campaa_3_2020.pdfIn PDF document text
    • http://ohota-ribalka.online/90647348907gdelr.pdfIn PDF document text
    • https://peliwotamo.weebly.com/uploads/1/3/5/3/135325711/64c7cd6723749.pdfIn PDF document text
    • https://wopokajam.weebly.com/uploads/1/3/0/8/130874492/9329430.pdfIn PDF document text
    • http://3203epworthcres.com/xukekisoximomezorovanerct1k.pdfIn PDF document text
    • https://rajomewebi.weebly.com/uploads/1/3/4/7/134712267/1995490.pdfIn PDF document text
    • https://jiketajaw.weebly.com/uploads/1/3/4/4/134464131/mupepomifazutiger.pdfIn PDF document text
    • http://beremoter.online/na_living_cleaneuzc6.pdfIn PDF document text
    • http://pojibuvuj.mygamesonline.org/29736556015.pdfIn PDF document text
    • https://katozela.weebly.com/uploads/1/3/0/8/130874493/3330574.pdfIn PDF document text
    • https://pajarozexukonom.weebly.com/uploads/1/3/1/4/131437235/gerobuxor_fajofedejadega_gipiluxinavuwo.pdfIn PDF document text
    • https://buwavazazaradig.weebly.com/uploads/1/3/3/9/133999961/madibezujuram.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://df6a9abb-74f3-47e1-b359-fe6d1019da36.filesusr.com/ugd/7921d2_d7fa5d338a6a4dd5aba0455f20480014.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/bulujono/tarafovapapegomedizosis.pdfIn PDF document text
    • https://db7841a4-af10-4990-a2be-f084cd4acbf6.filesusr.com/ugd/e3c460_2e85f438e3d94229937cba739468d5ae.pdf?index=trueIn PDF document text
    • https://0c6b7a74-1ca0-41da-943c-c268a208a416.filesusr.com/ugd/fef373_a850a7fa128242a096a58791e32bf628.pdf?index=trueIn PDF document text
    • https://12c9c681-cafc-4f88-93da-cb6f471fd49a.filesusr.com/ugd/f09a9d_a5ac18dd1a36499a8393d2c0ba5c438c.pdf?index=trueIn PDF document text
    • http://wutesejib.onlinewebshop.net/how_to_make_a_steel_column_in_revit.pdfIn PDF document text
    • https://c1bbde11-5cda-4f7c-8b74-b2fe90b484f5.filesusr.com/ugd/1c8c6c_d104cfc4a3284fdc901e8e657f03396b.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/megulu/84306284685.pdfIn 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_off0000e6c6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE6C6 5888 bytes
SHA-256: 215ddada66a0997e4748686ac3551e64fc7506381f0fc6c069dfd92fd3570c05
font_01_sfnt_off0000fab5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFAB5 11316 bytes
SHA-256: 33ba2a71361035f58a564fa385dc8558cb55914035c53eeb957f4fb195595e67