Malicious PDF — malware analysis report

Static analysis result for SHA-256 f5e8d45888100882…

MALICIOUS

PDF

27.4 KB Created: 2020-06-16 12:26:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2020-09-24
MD5: c1d7bee4f382e273542f462062c137c3 SHA-1: 0975c25673e0ba086c241cee9a0c81bb82d44514 SHA-256: f5e8d4588810088298f84e9070eec2ffcdc4384ecd4e6bb8a40eee595ff71702
96 Risk Score

Malware Insights

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

The PDF file contains a large number of external links, characteristic of a link farm, designed to redirect users to various websites. The heuristic 'PDF_SEO_LINK_FARM' specifically identifies this behavior. The embedded URLs point to potentially malicious content, and the ML classifier strongly indicates maliciousness. No scripts were extracted, but the structure of the PDF itself is the primary attack vector.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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://host49.carmichaelnl.com/uploads/1/3/0/7/130738769/130738769.html#tunturi+recumbent+exercise+bike PDF link annotation
    • http://mx.faithtabernaclefellowship.org/uploads/1/3/0/4/130488446/putipirot-vewojomibozude-duzakisekegibak-xopalixikezu.pdfIn PDF document text
    • http://dominguesandkane.com/uploads/1/3/1/0/131070895/xopipijabibamevasu.pdfIn PDF document text
    • http://bryanaungst.com/uploads/1/3/1/3/131383727/xemexolibobepukubev.pdfIn PDF document text
    • http://alexiskingtv.com/uploads/1/3/1/3/131398367/xusojomasogof.pdfIn PDF document text
    • http://thecenterofbeing.org/uploads/1/3/0/4/130489727/tuwuwuvupa-bumiserozufo-paxomonotipex.pdfIn PDF document text
    • http://wrebs.com/uploads/1/3/0/5/130542922/8774498.pdfIn PDF document text
    • http://pauldecaire.com/uploads/1/3/0/6/130621084/sivev_vuburat.pdfIn PDF document text
    • http://macrotopia.com/uploads/1/3/1/3/131398182/5429502.pdfIn PDF document text
    • http://dialtransportllc.com/uploads/1/3/0/2/130289453/376c90c9b3c049.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
    • http://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00004608.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x4608 8492 bytes
SHA-256: 95f6b50278e072256f3e2bd9ab616b17b959b3cf7919c14514aa7532bff54346