Malicious PDF — malware analysis report

Static analysis result for SHA-256 9e83711aa9c9ec1e…

MALICIOUS

PDF

37.0 KB Created: 2020-06-16 11:46:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2020-09-04
MD5: 1059bc673890f92263fbf94c30604835 SHA-1: db6912f0ab3a3ca3d672dc11743afb11f297975b SHA-256: 9e83711aa9c9ec1ecc76cbc7d5dfed78269365fec3842ac9319dfdbb0c0a4739
104 Risk Score

Malware Insights

MITRE ATT&CK
T1566.002 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains a link farm of external URLs, many of which point to other PDF files. This suggests a social engineering tactic to direct users to potentially malicious content. The heuristic 'PDF_SEO_LINK_FARM' strongly indicates this malicious intent. No scripts were extracted, limiting the analysis of direct payload execution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9982

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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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 http://laculturatokyo.com/uploads/1/3/0/6/130620515/130620515.html#english+workbook+class+9+cbse+answers+unit+6 PDF link annotation
    • http://hostmaster.thecoffeecupcakecompany.co.uk/uploads/1/3/1/6/131606373/a83d6e757.pdfIn PDF document text
    • http://restoredministry.net/uploads/1/3/1/4/131453031/4018928.pdfIn PDF document text
    • http://hostmaster.the-local-guide.co.uk/uploads/1/3/0/6/130620758/9591411.pdfIn PDF document text
    • http://hostmaster.kmsuk.net/uploads/1/3/0/6/130621022/tuted_zabakamivixedut_jarapip_juxopalugoxuwel.pdfIn PDF document text
    • http://emanandfiras.com/uploads/1/3/0/7/130739706/5180908.pdfIn PDF document text
    • http://dimensionaldifferences.studio/uploads/1/3/1/6/131636990/7266184.pdfIn PDF document text
    • http://wolfecityhomecoming.com/uploads/1/3/0/3/130379049/vigira.pdfIn PDF document text
    • http://stonetrustcommercial.com/uploads/1/3/0/2/130287482/92ada5f8ec.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://fedorahosted.org/lohitIn 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_off0000530b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x530B 10116 bytes
SHA-256: ea7b13b253e1aae888934d91191188563c223d2a5b9f493cf5655b3d29718951
font_01_sfnt_off000075e2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x75E2 5068 bytes
SHA-256: 0829d1c0dce8ac71930f0074ecd3cfc53df673feba7a3bf956d150812cae01ba