Malicious PDF — malware analysis report

Static analysis result for SHA-256 3eb68a98a342b827…

MALICIOUS

PDF

40.5 KB Created: 2020-08-16 00:43:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 18788f329369022aa50a69ddf0183db0 SHA-1: 0e75ed1a01d796c5bbd4186ec8e13969ae1325e7 SHA-256: 3eb68a98a342b827d23f9d1cc97ebd5a8fbbd1ef4f6752b184255bb03da9aff7
152 Risk Score

Malware Insights

MITRE ATT&CK
T1566.002 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains a critical heuristic firing for a malicious redirector link, pointing to 'ttraff.ru'. The document body, though heavily obfuscated, includes the same URL and text suggesting it's a lure for exam-related content. The presence of numerous other PDF links, many benign, indicates a link farm strategy. The ML classifier strongly flagged this PDF as malicious.

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://ttraff.ru/wb?keyword=trigonometry%20questions%20and%20answers%20for%20ssc%20exams%20pdf
    • http://ganatik.mingateachers.org/uploads/1/3/1/4/131437657/3437961.pdf
    • https://cdn.shopify.com/s/files/1/0432/3082/2555/files/ejercicios_para_aprender_ingles_gratis.pdf
    • https://cdn.shopify.com/s/files/1/0432/0801/6027/files/proyecto_ascensor_hidraulico.pdf
    • https://cdn.shopify.com/s/files/1/0432/1991/0813/files/16252977434.pdf
    • https://cdn.shopify.com/s/files/1/0436/7548/4313/files/jepowoxapuxowajurewi.pdf
    • https://cdn.shopify.com/s/files/1/0436/0683/5358/files/fajukaferolezovunakomuro.pdf
    • https://cdn.shopify.com/s/files/1/0427/4877/2508/files/28951174409.pdf
    • https://cdn.shopify.com/s/files/1/0433/6815/3239/files/6064889299.pdf
    • https://cdn.shopify.com/s/files/1/0430/5757/8138/files/texas_caviar_nutrition_information.pdf
    • https://cdn.shopify.com/s/files/1/0435/6295/9006/files/fopujowezatuwofavetilazid.pdf
    • https://cdn.shopify.com/s/files/1/0433/2378/5370/files/patoruvubivodig.pdf
    • https://cdn.shopify.com/s/files/1/0437/4927/7845/files/catia_manufacturing_tutorial_book.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 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00005d31.bin
71d92ea6138d3cd03f04c4b165b6be093716d43c980f74a8b09045c552f13294
pdf-font-stream PDF embedded font (sfnt) at offset 0x5D31 5780 bytes
font_01_sfnt_off000070db.bin
651b1121d45f3e72b3222410f1372fb2b18d9fe3f9352e09e8b134d9c9d4acea
pdf-font-stream PDF embedded font (sfnt) at offset 0x70DB 10528 bytes