Malicious PDF — malware analysis report

Static analysis result for SHA-256 7778b89c3e488233…

MALICIOUS

PDF

38.2 KB Created: 2020-06-16 11:43:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2020-09-24
MD5: 6141025c3e0435eb3e745ee6efe3f40c SHA-1: fc234c28f533f9032cf4bca096159edf2e72a105 SHA-256: 7778b89c3e4882331683bec86547755bfbd5fdbf74ab9cc2e082d7b8854b4e13
96 Risk Score

Malware Insights

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

The PDF document contains a large number of external links, many of which point to other PDF files hosted on various domains, suggesting a link farm or redirection mechanism. The document body, though partially corrupted, includes a URL that mimics a search result for a textbook solutions manual, likely a lure to encourage users to click on the embedded malicious links. The ML classifier strongly indicated maliciousness, and the PDF structure with numerous external links is a common tactic for distributing malware.

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://host64.carmichaelnl.com/uploads/1/3/0/7/130776514/130776514.html#financial+and+managerial+accounting+for+mbas+3rd+edition+solutions+manual PDF link annotation
    • http://wellnow212.com/uploads/1/3/0/2/130287295/mudosoku.pdfIn PDF document text
    • http://jenalexis.com/uploads/1/3/1/0/131070895/a5d340112911.pdfIn PDF document text
    • http://cpanel.accutypeservices.com/uploads/1/3/1/3/131380404/nuxabodulunutigasaj.pdfIn PDF document text
    • http://cpanel.lllofts.com/uploads/1/3/0/2/130291036/mukop.pdfIn PDF document text
    • http://happyfulfilledlife.com/uploads/1/3/0/7/130739936/2794498.pdfIn PDF document text
    • http://bghsboosters.org/uploads/1/3/1/4/131437331/wolezibesokulugolan.pdfIn PDF document text
    • http://myjgallagher.com/uploads/1/3/0/4/130476709/kijawukodumil.pdfIn PDF document text
    • http://resistefilm.com/uploads/1/3/0/7/130739686/8706780.pdfIn PDF document text
    • http://adentarussia.com/uploads/1/3/0/3/130313063/2bc33.pdfIn PDF document text
    • http://doubleheartsoapcompany.com/uploads/1/3/0/3/130312952/2612be8f6ac7.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn 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 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00006afe.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x6AFE 9844 bytes
SHA-256: aab581202d0d00033a50e103dc32498f6c96d41e4421d10a5580c1e4b9477a25