Malicious PDF — malware analysis report

Static analysis result for SHA-256 8b8d6f24f55b09d2…

MALICIOUS

PDF

79.1 KB Created: 2021-06-08 18:13:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-27
MD5: 79d26a3491b7e441f435d4d5d421d4f5 SHA-1: e914052307ffc8a40977d52cc598102ea0cd7ad1 SHA-256: 8b8d6f24f55b09d2e622e2b16990f0f60f9deb4d03a23a6dfe1dbed82280b998
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 ML classifiers and ClamAV, indicating a phishing or trojan threat. It contains a large number of external links, many pointing to disposable hosting, suggesting a link farm or SEO spam operation. The embedded content, though heavily obfuscated, appears to be part of this scheme to redirect users to potentially malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://archism.ru/pbw?utm_term=css+font+styles+list PDF link annotation
    • https://wapixetisabin.weebly.com/uploads/1/3/4/6/134685373/jufelen_gapoxobus.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4369518/normal_5fe8048a42726.pdfIn PDF document text
    • https://vixugusimuxomuj.weebly.com/uploads/1/3/0/9/130969476/363857d3.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4492536/normal_5fcf2f722390a.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4451932/normal_5fded46a3b4b1.pdfIn PDF document text
    • https://rudozusaviso.weebly.com/uploads/1/3/4/0/134041113/46682844948d.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4381094/normal_5fd19a9467a0e.pdfIn PDF document text
    • https://gibelugexafop.weebly.com/uploads/1/3/4/6/134687098/4470c.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4492253/normal_6005401ddf59f.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4446034/normal_602abc2a661af.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4484376/normal_602afc6c6240b.pdfIn PDF document text
    • https://xisuviwilizej.weebly.com/uploads/1/3/4/3/134320176/vejepusaka-waluj-kirexapa.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4458633/normal_60029fd7c9c28.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4447108/normal_5ff91e2d05de8.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4412607/normal_6026deaf821ea.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4463002/normal_6011e4ce3038e.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://komogabovuwa.pbworks.com/w/file/fetch/144808215/7173250495.pdfIn PDF document text
    • http://bofamawetodo.pbworks.com/f/myofascial_pain_and_dysfunction_the_trigger_point_manual.pdfIn PDF document text
    • http://gaguwufajij.pbworks.com/f/92530867654.pdfIn PDF document text
    • http://ganosidil.pbworks.com/f/58119489763.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
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000df1f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDF1F 4460 bytes
SHA-256: a27ee4f8b4616279f94c1232bbc1e8c7deb26f2127e1bd771ec1499b891fa747
font_01_sfnt_off0000ee6a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE6A 12208 bytes
SHA-256: f77fa47f4b156eb4ae54913d9102c5eb06ae71d6dda902fc8613469038d5e40b
font_02_sfnt_off0001183d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1183D 16568 bytes
SHA-256: 7737623bdd36147c1bc23cfbfc0fb31a32cbcf3064ab0f25ef1c34401f8e78b0