Malicious PDF — malware analysis report

Static analysis result for SHA-256 6711a123b6ff2e6f…

MALICIOUS

PDF

74.1 KB Created: 2021-05-19 13:14:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: b8138e4b740c9857c74c337e09304f38 SHA-1: 7bee9cddf3c7d135c89b88c1c45485993280d14b SHA-256: 6711a123b6ff2e6f05c57d9c7472310d299cbfc34a5f23dd6aced7948bd9d50a
156 Risk Score

Malware Insights

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

The PDF contains a large number of external links, identified by the PDF_SEO_LINK_FARM heuristic, pointing to various PDF files hosted on external services. The primary URL, https://seumenha.ru/strik, appears to be part of a malicious campaign. While no scripts were explicitly extracted, the nature of the link farm suggests a potential for hosting malicious content or phishing pages.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 5

  • 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-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://seumenha.ru/strik?utm_term=how+rare+is+intrahepatic+cholestasis+of+pregnancy
    • https://dawemewi.weebly.com/uploads/1/3/4/7/134747996/6d4759e.pdf
    • https://cdn-cms.f-static.net/uploads/4494893/normal_606cc6ec7f5f0.pdf
    • https://cdn-cms.f-static.net/uploads/4451736/normal_606e255412a0a.pdf
    • https://cdn-cms.f-static.net/uploads/4375894/normal_603486f8d057e.pdf
    • https://static.s123-cdn-static.com/uploads/4383806/normal_600959dbbeced.pdf
    • https://cdn-cms.f-static.net/uploads/4486363/normal_6029c72bb3975.pdf
    • https://litepuvib.weebly.com/uploads/1/3/4/7/134741427/6142510.pdf
    • https://kesesitevon.weebly.com/uploads/1/3/5/3/135317357/dagawetezavo.pdf
    • https://wofovado.weebly.com/uploads/1/3/1/8/131871653/456a6c.pdf
    • https://xajerunufunofe.weebly.com/uploads/1/3/1/3/131378991/6813088.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://s3.amazonaws.com/sezewu/bifajadewojewunumaz.pdf
    • https://s3.amazonaws.com/xesigeze/muzofunipem.pdf
    • https://s3.amazonaws.com/zagapaxa/xunabuza.pdf
    • https://s3.amazonaws.com/sojaxub/chrome_remote_desktop_latest_version_apk.pdf
    • https://s3.amazonaws.com/befafuni/58141464208.pdf
    • https://s3.amazonaws.com/popilo/dozixupusiwenibajijab.pdf
    • https://medlineplus.gov/genetics/condition/intrahepatic-cholestasis-of-pregnancy
    • 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_off0000e486.bin
0f0ced27f66ce599ebd069c24eebbdbe2238a49e3d40aeb6227ea1c20b9b84ab
pdf-font-stream PDF embedded font (sfnt) at offset 0xE486 5432 bytes
font_01_sfnt_off0000f715.bin
d5ad01f349a6bcd0d66b61483a5fdbb04873f8a2069a1ed6280183daaab64044
pdf-font-stream PDF embedded font (sfnt) at offset 0xF715 10516 bytes