Malicious PDF — malware analysis report

Static analysis result for SHA-256 af233889cff25e5a…

MALICIOUS

PDF

71.2 KB Created: 2020-11-22 01:44:32 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 5cadb883702d5a8c8442ad38646af2d3 SHA-1: 85abbb5eff39d684eb5babbbf15347997458cbba SHA-256: af233889cff25e5a8d2188a682e1072eb2f63f7efa40c58cdc38b3398a92f46e
156 Risk Score

Malware Insights

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

The PDF file was flagged by ClamAV as 'Pdf.Phishing.Trojan' and a machine learning classifier indicated a high probability of maliciousness. The heuristic 'PDF_SEO_LINK_FARM' indicates the presence of numerous external links, with one pointing to 'https://s3.amazonaws.com/jakujakula/29132300866.pdf', suggesting a tactic to distribute malicious content or phish users. The embedded URL 'https://trafftec.ru/aws?utm_term=imperative+form+french+changer' further supports the malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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://trafftec.ru/aws?utm_term=imperative+form+french+changer
    • https://sizukejagu.weebly.com/uploads/1/3/2/6/132681884/53940f43884d.pdf
    • https://cdn-cms.f-static.net/uploads/4382772/normal_5f8e4893682c6.pdf
    • https://cdn-cms.f-static.net/uploads/4408871/normal_5fae0de127178.pdf
    • https://cdn-cms.f-static.net/uploads/4376854/normal_5faa3fa458859.pdf
    • https://cdn-cms.f-static.net/uploads/4385850/normal_5fb6c09cc7248.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • http://www.daltonmaag.com/
    • https://s3.amazonaws.com/jakujakula/29132300866.pdf
    • https://s3.amazonaws.com/liwafo/tidubudubekiga.pdf
    • https://s3.amazonaws.com/somamere/56414315956.pdf
    • https://uploads.strikinglycdn.com/files/4e80bee0-2892-4b43-a76e-df95f13738e7/88349836029.pdf
    • https://s3.amazonaws.com/pusolefosex/23739600565.pdf
    • https://s3.amazonaws.com/tobobowu/autotask_psa_outlook_plugin.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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000cd55.bin
bcb14118f35cf6828d39e42e0854d8b72ce2d6e828ee9832a8e573fb979ef80e
pdf-font-stream PDF embedded font (sfnt) at offset 0xCD55 5004 bytes
font_01_sfnt_off0000de24.bin
14f04d377484ed7570396776cb393441909a811338adfeb71ee8727052035c16
pdf-font-stream PDF embedded font (sfnt) at offset 0xDE24 10600 bytes
font_02_sfnt_off0001022d.bin
9f355172d696dda274cac500966718f112ce76951f19577ac4888987ea6471b2
pdf-font-stream PDF embedded font (sfnt) at offset 0x1022D 4324 bytes