Malicious PDF — malware analysis report

Static analysis result for SHA-256 4bd70759427ffe98…

MALICIOUS

PDF

41.3 KB Created: 2020-05-23 17:52:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: eb0e2dd3cafa10bf4ede6e576e1a21d6 SHA-1: a3275161a4949e49494609731c86d9c1123a3f7d SHA-256: 4bd70759427ffe98cc2ad312d57effae9f72826910fe798e40013303096e8371
96 Risk Score

Malware Insights

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

The PDF contains a large number of embedded URLs pointing to domains that appear to be part of a link farm. The heuristic 'PDF_SEO_LINK_FARM' indicates that the PDF is designed to generate traffic by linking to numerous external PDF files. The ML classifier strongly flagged this PDF as malicious. The document body contains garbled text and some of the extracted URLs, reinforcing the link farm hypothesis.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9999

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://1pg.undesirable.us/uploads/1/3/0/7/130738944/130738944.html#who+makes+bauer+tools
    • http://calupadeltachi.org/uploads/1/3/0/8/130874519/wulekeladefo-pifimadiboxupuk.pdf
    • http://modesttruthmag.com/uploads/1/3/1/3/131378817/1399558.pdf
    • http://letsparti.org/uploads/1/3/0/6/130603772/pisenuga.pdf
    • http://boatinguae.net/uploads/1/3/0/5/130590508/jamaxog.pdf
    • http://gretalmay.com/uploads/1/3/0/8/130813747/pekutiz_wowovotef_wolikasexew_taliperipofa.pdf
    • http://mtscomics.com/uploads/1/3/0/5/130540208/vuzerawerovago.pdf
    • http://raisethewoofpethotel.info/uploads/1/3/1/4/131437099/xuriven-fogolef.pdf
    • http://pp-wohlmuth.de/uploads/1/3/1/4/131437423/xudedumu-vulosek-wuzozagu-wofamidagam.pdf
    • http://twincityphotography.com/uploads/1/3/0/8/130814830/9029853.pdf
    • http://paytonspretties.com/uploads/1/3/0/5/130589353/1573194.pdf
    • http://myskinnycoffeedrink.com/uploads/1/3/0/5/130539311/ditomirazamivuxuduz.pdf
    • http://jllcapitalmarketsregionstower.com/uploads/1/3/0/5/130589004/1be802f4bdbbde.pdf
    • http://amberg-electrical.com/uploads/1/3/0/8/130813025/5f8fb73da28f.pdf
    • http://158west.com/uploads/1/3/0/4/130483773/nubakujejone_xivajupudeda.pdf
    • http://mail.covidpolicytracker.nz/uploads/1/3/0/6/130604419/d126d24fb93e05a.pdf
    • http://grenadabla.org/uploads/1/3/0/6/130639905/luvasu-bagevobojaju-dawejodanu.pdf
    • http://mychicagoenterprises.com/uploads/1/3/0/5/130540134/zuxigadax.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_off000073fe.bin
045495bae983bd6b47108e920881dc3dade3b70a3953a829aec7d866074ef1dd
pdf-font-stream PDF embedded font (sfnt) at offset 0x73FE 11052 bytes