Malicious PDF — malware analysis report

Static analysis result for SHA-256 52844e56424d2baa…

MALICIOUS

PDF

47.7 KB Created: 2020-04-09 07:27:26 +03:00 Authoring application: wkhtmltopdf 0.12.1.4 (via Qt 4.8.6)
MD5: d7dc069169c8670bdfc60fcb2450ffff SHA-1: ea27cbd3f1c0aa251d3fcf0771ad8aef97b78963 SHA-256: 52844e56424d2baa8447d8655a8d35183f5392e2d670edcb339783ccf7014091
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, a technique commonly used for SEO manipulation or to distribute further malicious content. The ML classifier strongly indicated maliciousness. The primary attack pattern involves directing users to a vast array of external PDF files hosted on numerous domains, likely to obscure the ultimate malicious destination or to engage in link farming.

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://thespicecloset.com/uploads/1/3/0/5/130589132/130589132.html#asertividad+para+ni%C3%B1os+actividades
    • http://msaecr19.com/uploads/1/3/0/8/130813988/4005171.pdf
    • http://mylungmd.org/uploads/1/3/0/5/130589285/8422236.pdf
    • http://gracefullyglitteredcreations.com/uploads/1/3/0/4/130475883/d558b2bb211702.pdf
    • http://nursinghomepj.com/uploads/1/3/0/5/130588922/dofikazega.pdf
    • http://playdays-preschool.com/uploads/1/3/0/6/130622091/jepowabe.pdf
    • http://mygoddessessentials.com/uploads/1/3/1/3/131398215/6047892.pdf
    • http://resolveoh.com/uploads/1/3/0/3/130323552/fobugu.pdf
    • http://slowlifedoctor.com/uploads/1/3/0/6/130621932/feketuv.pdf
    • http://hitwriting.com/uploads/1/3/0/5/130590710/6adf4f9bfc2a2.pdf
    • http://krccenter.com/uploads/1/3/1/3/131384368/9393457.pdf
    • http://timdonovannow.com/uploads/1/3/0/9/130969298/2710408.pdf
    • http://wingsandwetlandswaterfowl.com/uploads/1/3/0/2/130291712/0a0b703bfb9a7fe.pdf
    • http://stuffbysteff.net/uploads/1/3/0/4/130489727/vazitefekube_fusuriraredunek_venev.pdf
    • http://wihempco.com/uploads/1/3/0/6/130605216/vevaputiwod_zoroxefone_lenipubasupes.pdf
    • http://kyinnavhda.com/uploads/1/3/0/9/130969356/93decaa5f.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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00006f63.bin
51265646061a7e8498d2eab6b301f14ea28e824045621188be208e3c5c7da911
pdf-font-stream PDF embedded font (sfnt) at offset 0x6F63 1984 bytes
font_01_sfnt_off00007851.bin
5689677f70aa7bf7162533bf2481a2791fbd6c016904a137d28a623b4919d086
pdf-font-stream PDF embedded font (sfnt) at offset 0x7851 9032 bytes
font_02_sfnt_off00009925.bin
6f5589cf1763d9b30124e401b8407e77d4f7b0da0f268c3843f690d2cc1178e8
pdf-font-stream PDF embedded font (sfnt) at offset 0x9925 16168 bytes