Malicious PDF — malware analysis report

Static analysis result for SHA-256 b4a891d1b577b818…

MALICIOUS

PDF

49.8 KB Created: 2020-03-06 15:59:34 +02:00 Authoring application: wkhtmltopdf 0.12.1.4 (via Qt 4.8.6) First seen: 2020-09-24
MD5: 96784b91c6903590be70423db00c4046 SHA-1: b60e76a51e5ff042f097993551ce3907365989dd SHA-256: b4a891d1b577b8185aa1a97e970aa8a56a7ea8348248272485b1f5f6ccc3b750
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF document contains a large number of embedded external links to other PDF files hosted on various domains. This pattern is indicative of SEO poisoning or a link farm designed to distribute malicious content or drive traffic to compromised sites. No scripts were extracted, and the document body is largely unreadable binary data, but the heuristic firings strongly suggest a malicious intent to redirect users to external resources.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 4

  • 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.
  • 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://74-123-75-216.mgwnet.com/uploads/1/3/0/2/130271158/130271158.html#uremia+in+end+stage+renal+disease PDF link annotation
    • http://shrinesearch.com/uploads/1/3/0/5/130588473/kukelujofaz.pdfIn PDF document text
    • http://himalayantales.co.uk/uploads/1/3/0/4/130476523/3979824.pdfIn PDF document text
    • http://nedcurcargo.com/uploads/1/3/0/2/130270747/tenofejaj.pdfIn PDF document text
    • http://mail.pabloardiles.com/uploads/1/3/0/6/130604441/lovexudavudivole.pdfIn PDF document text
    • http://mydhfastmandat.com/uploads/1/3/0/7/130775413/nirajeneluku_gazinezarem.pdfIn PDF document text
    • http://guardianprep.com/uploads/1/3/0/2/130289214/5797d5bbed932c7.pdfIn PDF document text
    • http://mx.dickinsoncd.org/uploads/1/3/0/7/130776823/4938e40a5d25.pdfIn PDF document text
    • http://northerndriveschool.com/uploads/1/3/0/5/130588169/ruvuzojerepopiku.pdfIn PDF document text
    • http://traininapp.com/uploads/1/3/0/8/130814121/gupuxo.pdfIn PDF document text
    • http://thejesusmission.com/uploads/1/3/0/4/130483302/c9371150d2d.pdfIn PDF document text
    • http://eddiecastle.com/uploads/1/3/0/2/130271097/kovusu_sudekubevamom.pdfIn PDF document text
    • http://www.harinet.net/uploads/1/3/0/3/130312934/2604937.pdfIn PDF document text
    • http://minatangoboutique.com/uploads/1/3/0/4/130436271/fadawelos.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

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000997e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x997E 8692 bytes
SHA-256: 5e47515d73595c33e4066cdff1dfca30be2685849e3bdbaaebf0ef8d1f029558