Malicious PDF — malware analysis report

Static analysis result for SHA-256 75ae5b17f71a2fd5…

MALICIOUS

PDF

52.0 KB Created: 2020-03-20 08:53:25 +02:00 Authoring application: wkhtmltopdf 0.12.1.4 (via Qt 4.8.6)
MD5: 8faa2edb57b79911a1791eca47192eb7 SHA-1: 213016805880b004fad267baa20b6636a1556dc5 SHA-256: 75ae5b17f71a2fd528e8b5bb24d9a1c805544420a3623c3a1f5685f0447b29f3
136 Risk Score

Malware Insights

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

The PDF contains a large number of external links to other PDF files hosted on various domains, identified as a link farm. The ML classifier strongly indicates maliciousness. The embedded links likely serve to distribute malware or engage in SEO spam, and the document itself contains garbled text and metadata from wkhtmltopdf, suggesting it was programmatically generated for this purpose.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 5

  • 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.
  • PDF link to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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://ankezimmermann.ca/uploads/1/3/0/2/130271038/130271038.html#funcion+matematica+del+circulo
    • http://slpprint.ca/uploads/1/3/0/2/130289426/76bfd3e3.pdf
    • http://smartonlinebookkeeping.net/uploads/1/3/0/5/130550847/warozutanorilu.pdf
    • http://mail.baanyingfamily.com/uploads/1/3/0/5/130551135/gikuzojat-sumuse-gaduti.pdf
    • http://www.asbuiltinformer.com/uploads/1/3/0/6/130604903/e7621244f7b2b.pdf
    • http://rem5vrlab.com/uploads/1/3/0/6/130603922/vozud.pdf
    • http://mandyodell.com/uploads/1/3/0/2/130287942/tukojob.pdf
    • http://pembrokepinesductcleaning.com/uploads/1/3/0/9/130969509/jukafejixi.pdf
    • http://moderntutoringandeducationservices.com/uploads/1/3/0/4/130490301/gunufonamenixarinusi.pdf
    • http://www.namonics.com/uploads/1/3/0/5/130551247/8807924.pdf
    • http://mx.passporttours.co.uk/uploads/1/3/0/6/130604126/degazow-gumomarezosobo.pdf
    • http://www.firtreeenterprises.com/uploads/1/3/0/7/130740087/kokoralobed.pdf
    • http://dadecompanies.net/uploads/1/3/0/2/130272936/tenod.pdf
    • http://icepic.club/uploads/1/3/0/6/130639563/5223481.pdf
    • http://organic-marijuana.net/uploads/1/3/0/7/130738720/ce1f179404.pdf
    • http://mymobilephysio.com/uploads/1/3/0/8/130814143/losezatogupako_wubedovofumew_sukizojoz.pdf
    • http://motivationalfactor.com/uploads/1/3/0/2/130289460/togom_nemamibuxaxin_dekodi_zuguxusu.pdf
    • http://engineeringally.com/uploads/1/3/0/6/130639899/2275283.pdf
    • http://stefstephapparel.com/uploads/1/3/0/6/130604230/83edf287cf2511f.pdf
    • http://beracahvalleyofblessings.com/uploads/1/3/0/5/130588452/rogus_latujasimoduz.pdf
    • http://theordinaryvoter.com/uploads/1/3/0/4/130488584/9510818.pdf
    • http://tobiasfate.com/uploads/1/3/0/9/130969391/c01685a2ec1c7.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • 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/
    • https://fedoraproject.org/wiki/Licensing/LiberationFontLicense
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00007e01.bin
66bce0d4928344dccde6aa15e52f1a371388a47df0f72d6ae14e2c8a3a7f1fe7
pdf-font-stream PDF embedded font (sfnt) at offset 0x7E01 9408 bytes
font_01_sfnt_off0000a03d.bin
a1917c614ec7f25b8d1fa2079fee512d1fdc400f3d8bbc68a3ddf734634b1df3
pdf-font-stream PDF embedded font (sfnt) at offset 0xA03D 3044 bytes
font_02_sfnt_off0000aaf5.bin
e8397047731bfd4629467185c5d3107524dee4d99a7520945325aeb852477b6c
pdf-font-stream PDF embedded font (sfnt) at offset 0xAAF5 16064 bytes