Malicious PDF — malware analysis report

Static analysis result for SHA-256 84c379a221e6dd72…

MALICIOUS

PDF

87.5 KB Created: 2020-06-04 07:18:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 1845b517afcc2e3cfa7c1a6aa5bad371 SHA-1: 5e2c27307c27cf8fb67e1fa896c7fa1194dec2c7 SHA-256: 84c379a221e6dd72666bbd64f8ed3555a300a4ff2c909c91876aa3e976373054
96 Risk Score

Malware Insights

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

The PDF file contains a large number of external links, many of which point to domains that appear to be part of a link farm designed to host malicious content. The document body, though heavily obfuscated, contains text related to 'Elementary statistics 9th edition' and the authoring application 'wkhtmltopdf', suggesting a lure to disguise the malicious intent. The ML classifier strongly flagged this PDF as malicious, indicating a high probability of malicious activity.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://caneshakatreseprenci.com/uploads/1/3/0/2/130289553/130289553.html#elementary+statistics+9th+edition
    • http://ocmunc.com/uploads/1/3/0/2/130289733/bd23a9c7b496.pdf
    • http://center4centerstage.com/uploads/1/3/0/7/130739951/xelapipozowazidigel.pdf
    • http://server-07.gaskeun.com/uploads/1/3/0/7/130775916/625dfcfc4b7d3.pdf
    • http://autodiscover.phimi.pt/uploads/1/3/1/4/131438438/goxaloxire-gasaw-rovizefa-pawagunotenuji.pdf
    • http://mail.intrinsology.com/uploads/1/3/0/6/130639329/juseketogepog-burutu.pdf
    • http://radiomajaja.com/uploads/1/3/1/4/131438761/jepeti.pdf
    • http://caneshakatreseprenci.com/uploads/1/3/0/2/130289553/terms.html
    • http://caneshakatreseprenci.com/uploads/1/3/0/2/130289553/dmca.html
    • http://caneshakatreseprenci.com/uploads/1/3/0/2/130289553/policy.html
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://tefivebofoge.files.wordpress.com/2020/06/59989877172.pdf
    • https://xisalab.files.wordpress.com/2020/06/rifol.pdf
    • https://bakesigoru.files.wordpress.com/2020/06/fojajo.pdf
    • https://pojolukowo.files.wordpress.com/2020/06/6809768429.pdf
    • https://kisawas.files.wordpress.com/2020/06/jinerezapilunuje.pdf
    • https://zoruwebi.files.wordpress.com/2020/06/4161004945.pdf
    • https://narofava.files.wordpress.com/2020/06/1553086319.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/
    • http://scripts.sil.org/OFL

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00012b24.bin
34219290a08ee5ae2ff565029ac558905771ff1705b525edc93246562d8f4047
pdf-font-stream PDF embedded font (sfnt) at offset 0x12B24 11492 bytes