Malicious PDF — malware analysis report

Static analysis result for SHA-256 a3afd7ff2cf7f584…

MALICIOUS

PDF

39.1 KB Created: 2020-06-05 05:09:02 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 1aa833ab356fa9809afb2b5c56e53a12 SHA-1: a9c83010388fcf47e8634d7fe5a733a108c76d2e SHA-256: a3afd7ff2cf7f58429ead0fcba6d784918065d2c4782971735241f69dc906d10
94 Risk Score

Malware Insights

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

The PDF file contains a large number of external links, many of which are SEO-optimized and point to other PDF files. This behavior is indicative of a link farm designed to attract users searching for specific content, such as 'mistborn trilogy epub free download'. The ML classifier strongly flagged this PDF as malicious, supporting the conclusion that it is part of a malicious distribution scheme.

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://youngmindsmatteradelaide.com/uploads/1/3/0/9/130969497/130969497.html#mistborn+trilogy+epub+free+download
    • http://hostmaster.spiritofthehorseshow.com/uploads/1/3/0/6/130620715/jujazisotu.pdf
    • http://x0768597xstreamtravel.xsideas.com/uploads/1/3/0/9/130968911/lilalajezog-pajewexelotop.pdf
    • http://organicbabyfoodshop.com/uploads/1/3/0/8/130813869/moliwo.pdf
    • http://taramctighe.com/uploads/1/3/1/8/131871587/rojadududuvizot-tupesajelap-fadunekubedadon.pdf
    • http://marylandcivilairpatrol.org/uploads/1/3/1/4/131437982/rejopelu-gidifeduzujupe-gawusuler-guwisopojeruge.pdf
    • http://dresurgical.net/uploads/1/3/0/4/130488412/7925252.pdf
    • http://nhsaustraliamedicalcentre.com/uploads/1/3/1/4/131437845/5086921.pdf
    • http://12stonesmoldcleaning.com/uploads/1/3/0/9/130969999/5df9c29ddfeb5c.pdf
    • http://youngmindsmatteradelaide.com/uploads/1/3/0/9/130969497/terms.html
    • http://youngmindsmatteradelaide.com/uploads/1/3/0/9/130969497/dmca.html
    • http://youngmindsmatteradelaide.com/uploads/1/3/0/9/130969497/policy.html
    • https://greatebook-
    • https://kajunomifoj.files.wordpress.com/2020/06/95533650331.pdf
    • https://ranizofotebo.files.wordpress.com/2020/06/9035250041.pdf
    • https://danadaderano524270775.files.wordpress.com/2020/06/goxulewipupadodugeru.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/

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00005438.bin
d679e5a7834156721447bf08d2224a4c277414e0ea8b95ffa0d9685b8a258b43
pdf-font-stream PDF embedded font (sfnt) at offset 0x5438 11652 bytes
font_01_sfnt_off00007b36.bin
3f70697d8cfd0b9becff5adcad726f9ffedcc5d773cc6f7abbcc82b2f8034994
pdf-font-stream PDF embedded font (sfnt) at offset 0x7B36 16164 bytes