Malicious PDF — malware analysis report

Static analysis result for SHA-256 4804f3e5d0b36f90…

MALICIOUS

PDF

43.0 KB Created: 2020-03-10 05:05:18 +02:00 Authoring application: wkhtmltopdf 0.12.1.4 (via Qt 4.8.6) First seen: 2020-09-24
MD5: 7acae92bb9e0d2bb7909e252181f78de SHA-1: f43c529600011194b89b040b981d03dda66bb168 SHA-256: 4804f3e5d0b36f90b6c2ee1e780123c55825f07a7997be69fcd64d59ff9c9e93
96 Risk Score

Malware Insights

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

This PDF document contains a large number of external links, many of which point to other PDFs hosted on various domains. The primary URL, http://74-123-72-53.mgwnet.com/uploads/1/3/0/9/130969403/130969403.html#f+test+anova+table+pdf, appears to be a lure to disguise the malicious intent. The ML classifier strongly indicates maliciousness, and the PDF structure suggests a link farm designed to distribute further malicious content or phish users.

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://74-123-72-53.mgwnet.com/uploads/1/3/0/9/130969403/130969403.html#f+test+anova+table+pdf PDF link annotation
    • http://www.autoimmunejourney.org/uploads/1/3/0/5/130541950/vuwifixud.pdfIn PDF document text
    • http://kristenfong.info/uploads/1/3/0/3/130323765/julowitinobo.pdfIn PDF document text
    • http://mail.ryanbrownmusic.com/uploads/1/3/1/0/131070334/1021920.pdfIn PDF document text
    • http://grasshoppersprings.com/uploads/1/3/0/2/130270985/vivimanurita.pdfIn PDF document text
    • http://foreclosedtnhomes.com/uploads/1/3/0/5/130589198/fiwiz.pdfIn PDF document text
    • http://valcom.tv/uploads/1/3/0/6/130622042/8597775.pdfIn PDF document text
    • http://hostmaster.lula.site/uploads/1/3/0/6/130620966/9594747.pdfIn PDF document text
    • http://writersink85.com/uploads/1/3/0/7/130739663/6635221.pdfIn PDF document text
    • http://hillbillynationalbank.com/uploads/1/3/0/8/130813738/jetitekipeje-pubebizok-mewudidivibe-rugikoral.pdfIn PDF document text
    • http://cardeocreative.com/uploads/1/3/0/7/130775047/23928813f78386.pdfIn PDF document text
    • http://vreedy.shop/uploads/1/3/0/7/130739128/c1fbec52.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • https://fedoraproject.org/wiki/Licensing/LiberationFontLicenseIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000072d9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x72D9 8520 bytes
SHA-256: 81853efcad072664b4382a4188be49b0375bb4a6c019ef312ef81fd40d4c9976
font_01_sfnt_off000093ba.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x93BA 2736 bytes
SHA-256: ccd4c16be78461455bc416a6b2a82209edd949535a8ea342684372e9e7370a0b