Malicious PDF — malware analysis report

Static analysis result for SHA-256 849af3bfe2cbe703…

MALICIOUS

PDF

74.3 KB Created: 2021-06-11 07:00:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-29
MD5: 1db4de014a8504c650fb98da29276d99 SHA-1: 1df9fac7333868b180b921aa8896580e7fdfb786 SHA-256: 849af3bfe2cbe7034ff31486825f091eb593ac0339ee513a6d67fa77d76a78b2
186 Risk Score

Malware Insights

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

This PDF file was identified as malicious by ClamAV and an ML classifier, exhibiting characteristics of a link farm. It contains a large number of external URIs, many hosted on disposable domains, suggesting an attempt to manipulate search engine results or redirect users to malicious content. The primary attack pattern involves embedding numerous external links within the document.

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://wastran.ru/pbw?utm_term=unsupervised+learning+deep+neural+networks PDF link annotation
    • https://kutisujazuj.weebly.com/uploads/1/3/4/6/134625744/f0b0694041705.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4367646/normal_601de139444d0.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4443809/normal_5fcc7296c17f3.pdfIn PDF document text
    • https://namovanuzo.weebly.com/uploads/1/3/1/6/131606642/75d3adce.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4417408/normal_60baae1743cfa.pdfIn PDF document text
    • https://saxeguwub.weebly.com/uploads/1/3/1/4/131406831/lopopobatav.pdfIn PDF document text
    • https://wegekasi.weebly.com/uploads/1/3/4/6/134678838/912af7bc.pdfIn PDF document text
    • https://povitopol.weebly.com/uploads/1/3/4/6/134648875/324607.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4417207/normal_603d045e7b37e.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4421615/normal_6003acb810834.pdfIn PDF document text
    • https://sosojisizavawov.weebly.com/uploads/1/3/1/4/131454692/8155391.pdfIn PDF document text
    • https://gigufeti.weebly.com/uploads/1/3/4/6/134633464/sukivixupefadoj-zugon-fiwitaso-juvexixasufeveg.pdfIn PDF document text
    • https://kedepojab.weebly.com/uploads/1/3/0/7/130739947/27f3400ac.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4407302/normal_5fc7306dcb346.pdfIn PDF document text
    • https://vavimogazoru.weebly.com/uploads/1/3/5/9/135968849/dozaweranu.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://uploads.strikinglycdn.com/files/2799ec86-3226-4e64-9196-3766c1afe9f2/67826246405.pdfIn PDF document text
    • http://pibadaro.pbworks.com/f/kibozabu.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/530d3b28-48b8-400c-acf3-520f7af0e837/best_bitcoin_mining_app_for_windows.pdfIn PDF document text
    • http://wusagem.pbworks.com/f/vibaxegajafejuloropadubav.pdfIn PDF document text
    • http://taxexuwej.pbworks.com/w/file/fetch/144647466/wuvetufuwosulelovifawusus.pdfIn PDF document text
    • http://kuzukiwirimi.pbworks.com/w/file/fetch/144938235/donudes.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_off0000e5c5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE5C5 5336 bytes
SHA-256: 271ae81d0450acc473aa94e30a4f3a1dcc7a3f73a7ffa864d42c4e9db6f4a2cc
font_01_sfnt_off0000f810.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF810 10476 bytes
SHA-256: 73e25e873cf1377cfef88b1b75ee12de87f07503fb7eee83c1487b4485a879ba