Malicious PDF — malware analysis report

Static analysis result for SHA-256 c9f1fa2de64829de…

MALICIOUS

PDF

39.9 KB Created: 2020-03-29 14:19:42 +03:00 Authoring application: wkhtmltopdf 0.12.1.4 (via Qt 4.8.6)
MD5: 15b249f97d58463d705ac33738467132 SHA-1: 34e240f08dbe87c4df2876407761c1a7213ef717 SHA-256: c9f1fa2de64829de29b1896da717fde5d01fb1cfdbc67a59e3da5935b014c1c3
94 Risk Score

Malware Insights

MITRE ATT&CK
T1566.002 Phishing: Spearphishing Attachment T1204.002 Malicious File: Malicious File

The PDF file contains a large number of external links, many of which point to other PDF files, indicating a link farm designed to artificially boost search engine rankings. The document body, though partially corrupted, suggests a lure for a 'digital control systems textbook free download'. The ML classifier strongly flagged this PDF as malicious, and the heuristic firings confirm the presence of a mass external PDF link farm.

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://carpetcleancary.com/uploads/1/3/0/5/130544091/130544091.html#digital+control+systems+textbook+free+download
    • http://dlgunsmithing.net/uploads/1/3/0/4/130435598/janijase.pdf
    • http://atelierquimera.com/uploads/1/3/0/6/130639491/satubupuv-mevojen-juvazivu.pdf
    • http://canmoreappliancerepair.com/uploads/1/3/0/7/130775635/11e0000a5a43b9.pdf
    • http://steveanddannythompson.com/uploads/1/3/0/2/130289377/e60f19bf.pdf
    • http://austinmaloney.net/uploads/1/3/0/5/130589331/3592588.pdf
    • http://entaoproductions.com/uploads/1/3/0/6/130621225/7160894.pdf
    • http://myfavfork.com/uploads/1/3/1/0/131070925/495facc1.pdf
    • http://hedyting.ca/uploads/1/3/0/7/130776823/kifenix-nukalizoku.pdf
    • http://cityfarmindustries.com/uploads/1/3/0/7/130775622/3357244.pdf
    • http://clvr-cv.com/uploads/1/3/0/3/130323453/49ec85f125aca6.pdf
    • http://sprexperientiallearning.com/uploads/1/3/0/4/130476255/8042676.pdf
    • http://surgeryprocess.com/uploads/1/3/0/3/130379741/619b405fc64fc8e.pdf
    • http://janefaily.com/uploads/1/3/0/5/130540104/bikumikufo.pdf
    • http://holyboidesigns.com/uploads/1/3/0/3/130313383/jilox.pdf
    • http://walkingmountain.net/uploads/1/3/0/9/130969974/40def0bdca02fa.pdf
    • http://kellettcommunications.com/uploads/1/3/0/6/130639224/1526547.pdf
    • http://kkandooenglish.com/uploads/1/3/0/8/130813496/renipatitupidom-jovirogexisabi-tusesodomofavu.pdf
    • http://teknikdagen.se/uploads/1/3/0/7/130775742/9106161.pdf
    • http://zteaches.com/uploads/1/3/0/6/130640031/a1b2364d.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 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00007281.bin
71a1c8df42b0e58cb02f7a8c8f9c96641bf2990fdf925fbbd8263f860efe20f7
pdf-font-stream PDF embedded font (sfnt) at offset 0x7281 8488 bytes