Malicious PDF — malware analysis report

Static analysis result for SHA-256 e021891fba73fdbc…

MALICIOUS

PDF

75.9 KB Created: 2020-10-05 01:31:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-27
MD5: a7a131b3311d2d64b2d5c7d2bff72577 SHA-1: 6f6795dd686ee065e33895e23dd409dfa6a97e7f SHA-256: e021891fba73fdbcbe75a158b9148fb5eb995e5b9ed509c20492a5034f4b6e1c
182 Risk Score

Malware Insights

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

The PDF contains a large number of embedded links, with heuristics indicating that it is a link farm designed to redirect users to potentially malicious sites. One URL, https://cctraff.ru/strik?keyword=boky+mainty+pdf+libres, is specifically flagged as a malicious redirector. The ML classifier also strongly indicated maliciousness. The document body contains obfuscated text and a URL that appears to be part of the link farm.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9949

Heuristics 4

  • PDF links to known malicious redirector infrastructure critical PDF_MALICIOUS_REDIRECTOR_LINK
    PDF contains a clickable URI to redirector infrastructure used by a known malicious PDF SEO/adware delivery campaign. These documents typically rely on user interaction and redirect chains rather than a PDF parser vulnerability.
  • 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.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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 https://cctraff.ru/strik?keyword=boky+mainty+pdf+libres In PDF document text
    • https://site-1036973.mozfiles.com/files/1036973/xigisawogobovirepimef.pdfIn PDF document text
    • https://site-1037283.mozfiles.com/files/1037283/nedukenesopajogemapenoj.pdfIn PDF document text
    • https://site-1038788.mozfiles.com/files/1038788/tajakifetujilitiwewamali.pdfIn PDF document text
    • http://files.khylor.com/uploads/1/3/1/4/131483386/3901722.pdfIn PDF document text
    • http://sulunu.partnersinrelief.com/uploads/1/3/1/8/131871761/laverijadamajevu.pdfIn PDF document text
    • http://berav.pinklabelfashion.com/uploads/1/3/1/4/131453741/6db4c2e0f37c.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://cdn.shopify.com/s/files/1/0462/7732/9056/files/gaggia_espresso_machine_reviews.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0465/4222/5566/files/btd6_deflation_guide.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0496/6884/9821/files/90_mile_beach_australia.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/2bd72945-48c1-4958-829c-9eb2ead562f4/79777513646.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/c7e73628-6822-4273-a27e-e4b710abe1ec/27545223484.pdfIn PDF document text
    • http://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f964.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF964 5540 bytes
SHA-256: f505346bbfcb68378c1ab00154c6f21f3558d706eaf20fbbcf51d53052527f20
font_01_sfnt_off00010c2f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10C2F 12492 bytes
SHA-256: 6b0a7ae837911032da2891f2eabcea6210d4b3937f2729d57a63f46f8162c11a