Malicious PDF — malware analysis report

Static analysis result for SHA-256 d5b9a30d0c54df2d…

MALICIOUS

PDF

68.4 KB Created: 2020-11-29 07:18:51 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 735c2c93ffdcfd47b75fefb8981bf48b SHA-1: 729a7884cbe35b76e3d3d7efc24d1d1fd2c7278b SHA-256: d5b9a30d0c54df2d194693e3fb880537bc301d30ee667e4644f73cca70f92a62
244 Risk Score

Malware Insights

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

This PDF file was flagged by multiple heuristics as malicious, including a critical finding for linking to known malicious redirector infrastructure and a large number of external PDF links, suggesting a link farm. The ML classifier also strongly indicated maliciousness. The embedded URLs and the nature of the heuristics point towards a phishing or SEO manipulation attack pattern. No scripts were extracted, but the PDF structure itself facilitates the malicious redirection.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

Heuristics 6

  • PDF links to known malicious redirector infrastructure critical PDF_MALICIOUS_REDIRECTOR_LINK
    PDF contains a clickable URI to redirector infrastructure used by a known malicious PDF SEO/adware delivery campaign. These documents typically rely on user interaction and redirect chains rather than a PDF parser vulnerability.
  • 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.
  • 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 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.
  • 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://cctraff.ru/strik?utm_term=corona+del+mar+weather+averages
    • https://mesedegusi.weebly.com/uploads/1/3/4/6/134600151/4046585.pdf
    • https://cdn-cms.f-static.net/uploads/4368489/normal_5fb4e6e01cedd.pdf
    • https://kegegofelev.weebly.com/uploads/1/3/2/6/132681159/kaneror_fimeno_sumukojur_lorekitefiwurew.pdf
    • https://cdn-cms.f-static.net/uploads/4367667/normal_5f972ba4c48f8.pdf
    • https://lexodedibipi.weebly.com/uploads/1/3/4/6/134683920/legugotunave-xifapif-jozavove-gelowabawoj.pdf
    • https://cdn-cms.f-static.net/uploads/4366339/normal_5f878ee1474ef.pdf
    • https://gaxirakim.weebly.com/uploads/1/3/4/6/134605205/3675172.pdf
    • https://fijuwokokaku.weebly.com/uploads/1/3/4/3/134382009/a31fc32a87a2.pdf
    • https://meboguvogo.weebly.com/uploads/1/3/1/4/131437667/lisibojuk.pdf
    • https://bafipiwefewojex.weebly.com/uploads/1/3/4/5/134576197/muvexajigosozo_fukezixozidub_busebilijone_wabugap.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://s3.amazonaws.com/zijivevip/country_music_fake_book_free.pdf
    • https://s3.amazonaws.com/pujirageg/download_gta_5_installer_pc.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://scripts.sil.org/OFL

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ced6.bin
22f7ba50fd3c444449908dc5792f7f2ddb85bf3100c0495eab37fe1a48707db1
pdf-font-stream PDF embedded font (sfnt) at offset 0xCED6 5296 bytes
font_01_sfnt_off0000e0c3.bin
a7c26a03b1c6c367bb7381cab708c83914057bccd154391b545bba56070ec506
pdf-font-stream PDF embedded font (sfnt) at offset 0xE0C3 10668 bytes