Malicious PDF — malware analysis report

Static analysis result for SHA-256 b8dc9694adb2a7aa…

MALICIOUS

PDF

38.0 KB Created: 2020-03-20 11:07:26 +02:00 Authoring application: wkhtmltopdf 0.12.1.4 (via Qt 4.8.6)
MD5: 22d0be166f8385cb77e6d2d903ae064a SHA-1: de1de1455a4e7fcdbc365d18fd75432d1a4660e6 SHA-256: b8dc9694adb2a7aa3e50fcc2507b09406568686424d35a770a78cb0231bf8882
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.002 Spearphishing Attachment T1059.001 PowerShell

The PDF file contains a large number of external links, many of which are numerically or generically named, suggesting a link farm for SEO manipulation or to host malicious content. The document body, though malformed, contains text related to 'exponential functions growth and decay worksheet' and references the wkhtmltopdf tool, indicating a potential lure. The ML classifier strongly flagged this PDF as malicious. The primary attack pattern involves directing users to a network of suspicious URLs, likely for phishing or malware delivery.

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://dottis.ch/uploads/1/3/0/8/130874325/130874325.html#exponential+functions+growth+and+decay+worksheet
    • http://riverbendbaptist.net/uploads/1/3/0/3/130324419/87a306855ca197.pdf
    • http://www.lawintechdiversity.com/uploads/1/3/0/6/130603818/xijavu-garivufarovubu-divajedus-tipirawujibose.pdf
    • http://mindmeltgames.com/uploads/1/3/0/7/130775643/259265.pdf
    • http://sheffieldcctvsystems.com/uploads/1/3/0/5/130539021/afef7c0bcd4837a.pdf
    • http://divinevirgin.com/uploads/1/3/0/5/130588370/7898cc61.pdf
    • http://nutritionavenuefitness.com/uploads/1/3/0/7/130775732/zoranetubufu-woxituf.pdf
    • http://apply.vibot.org/uploads/1/3/1/0/131069906/9592096.pdf
    • http://villagecafehampstead.com/uploads/1/3/0/6/130620704/fosesijavomome.pdf
    • http://cretanmaliaredesign.devsite-1.com/uploads/1/3/0/2/130272513/6594875.pdf
    • http://www.hamiltonsguttercleaning.com/uploads/1/3/0/6/130639741/86d096c0d8.pdf
    • http://rt1tj.dtmgt.com/uploads/1/3/0/3/130313274/65a53a.pdf
    • http://rldegraffenried.com/uploads/1/3/0/5/130540869/707e992210.pdf
    • http://tiffanygiardina.net/uploads/1/3/0/5/130589460/6483558.pdf
    • http://ketonedietpills.org/uploads/1/3/0/4/130491319/tuzetogexumude.pdf
    • http://vakantiehuis-in-de-ardennen.nl/uploads/1/3/0/5/130547207/tijopumidadopu.pdf
    • http://mail.georgiacollies.com/uploads/1/3/0/6/130620142/tukulabakekatoweban.pdf
    • http://www.startearningwithjimmyq.com/uploads/1/3/0/7/130776444/fojoso.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_off000067e8.bin
a62af5b66894c98213c17eb5717215326daf75617cc02d6a8d1a380f59850136
pdf-font-stream PDF embedded font (sfnt) at offset 0x67E8 8528 bytes