Malicious PDF — malware analysis report

Static analysis result for SHA-256 b303653f88d2f8a1…

MALICIOUS

PDF

49.0 KB Created: 2020-10-30 14:52:01 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: fe2d73c1351368463215b647a48d2645 SHA-1: 93b9830172876e44f82043064341db28f9f74fad SHA-256: b303653f88d2f8a1e38586893c120fc2303fe2866418dc8b20eb261cd1816957
154 Risk Score

Malware Insights

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

This PDF file was flagged as malicious by a machine learning classifier and contains multiple embedded links. One of these links, 'https://cctraff.ru/strik?keyword=intj+guide+reddit', points to known malicious redirector infrastructure, indicating a phishing or scam attempt. The document body, though heavily obfuscated, contains the same URL, suggesting it's the primary lure. The presence of numerous external PDF links further supports the classification as a link farm designed to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

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.
  • 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 https://cctraff.ru/strik?keyword=intj+guide+reddit
    • https://cdn-cms.f-static.net/uploads/4387417/normal_5f8fcb7255bd0.pdf
    • https://cdn-cms.f-static.net/uploads/4376854/normal_5f89e2a2d3f87.pdf
    • https://cdn-cms.f-static.net/uploads/4383680/normal_5f9236da55b8d.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://cdn.shopify.com/s/files/1/0433/9171/3447/files/8118743016.pdf
    • https://s3.amazonaws.com/gupuso/82678311581.pdf
    • https://s3.amazonaws.com/bugutaj/water_pressure_booster_pump.pdf
    • https://uploads.strikinglycdn.com/files/7f4cc188-4e20-4649-9f5a-a88aafbd6c91/muninuzolipuvejofik.pdf
    • https://cdn.shopify.com/s/files/1/0432/9419/5870/files/asthma_causes_symptoms_treatment_and_prevention.pdf
    • https://s3.amazonaws.com/vaxebisapesi/intolerancia_alimentaria_definicion.pdf
    • https://s3.amazonaws.com/tobobowu/pasar_archivos_a_word_sin_programas.pdf
    • https://uploads.strikinglycdn.com/files/a6d8996a-52d0-4900-9c7f-b389db5f717a/kekilutapizanidabufaz.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 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000832d.bin
e75b6b6e2bbe36a86be61c7ae612502e1e85d913ba086276c699e933b7574776
pdf-font-stream PDF embedded font (sfnt) at offset 0x832D 4588 bytes
font_01_sfnt_off000092db.bin
e0a639e33785d563b6cb087da6b7c76df34a095d5a426fc24d91f40defab5494
pdf-font-stream PDF embedded font (sfnt) at offset 0x92DB 10728 bytes