Malicious PDF — malware analysis report

Static analysis result for SHA-256 87e7c09d9f8644f4…

MALICIOUS

PDF

33.2 KB Created: 2020-05-18 14:39:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2020-09-24
MD5: efd62ae9e7aa5d6631871eedb6eabd5c SHA-1: b235120b690e2a18f20880c3da79713a6aced4db SHA-256: 87e7c09d9f8644f4ec9204da6b7a2ef2e86c3f5a7f300d66de265a491578e2da
96 Risk Score

Malware Insights

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

The PDF file contains numerous external links, many of which are structured as SEO link farms, suggesting a phishing or malicious redirection attempt. The document body, though partially corrupted, contains the text "Manual writer salary", likely a lure to entice users to click on the embedded malicious URLs. The ML classifier strongly flagged this PDF as malicious, indicating a high probability of harmful intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9952

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://hope-post.com/uploads/1/3/0/7/130739970/130739970.html#manual+writer+salary PDF link annotation
    • http://gosafetech.com/uploads/1/3/1/3/131379262/a4edbd246280b.pdfIn PDF document text
    • http://naturalorganicbeautyhealth.org/uploads/1/3/0/8/130874382/3669751.pdfIn PDF document text
    • http://kultrclub.com/uploads/1/3/1/6/131606594/431787.pdfIn PDF document text
    • http://tuarea.eco/uploads/1/3/0/6/130604983/4071172.pdfIn PDF document text
    • http://xavierernstnp.com/uploads/1/3/0/6/130604529/worebirit_vumokipakawaxa_fubog_karumezave.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_off0000544e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x544E 11188 bytes
SHA-256: c5f9059228b61d73357de993150338ffff83a38cd76357671d2f5d0608cb0e5e