Malicious PDF — malware analysis report

Static analysis result for SHA-256 a5d83c2a3d3094fd…

MALICIOUS

PDF

42.4 KB Created: 2020-08-21 17:48:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: f3fc372b6f5aadfed96e54b19bf3d2f1 SHA-1: c153b5ace2bb457e474e8d8e240a236d181d8c48 SHA-256: a5d83c2a3d3094fd42f547d9dbf1948cbd26b4e401eec08c6762fbc6679a7f4e
152 Risk Score

Malware Insights

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

The PDF was flagged as malicious by a machine learning classifier and contains a critical heuristic indicating it links to known malicious redirector infrastructure. The document body, though heavily obfuscated, contains URLs that are part of a link farm, with one specifically pointing to a redirector. This suggests the primary purpose is to lure 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://ttraff.ru/pify?keyword=student+centered+learning+theory+pdf
    • http://files.robpartis.co.uk/uploads/1/3/0/7/130775520/d43ef80b31b09eb.pdf
    • http://getono.phsgolf.net/uploads/1/3/0/7/130775380/4763031.pdf
    • https://cdn.shopify.com/s/files/1/0431/3546/7669/files/soferupinugurenunasodebo.pdf
    • https://cdn.shopify.com/s/files/1/0431/8475/0747/files/kudotexesetuguxawarinag.pdf
    • https://cdn.shopify.com/s/files/1/0439/5266/8830/files/52269046143.pdf
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/tugomedimugatusigoxafif.pdf
    • https://cdn.shopify.com/s/files/1/0433/9957/7756/files/58561736980.pdf
    • https://cdn.shopify.com/s/files/1/0456/8360/5663/files/android_bundle_fragment_example.pdf
    • https://cdn.shopify.com/s/files/1/0434/7658/2552/files/bijadovuzofugifubowani.pdf
    • https://cdn.shopify.com/s/files/1/0465/3491/8302/files/pabejaligukukufaga.pdf
    • https://cdn.shopify.com/s/files/1/0440/7102/6853/files/introductory_to_circuit_analysis_13th_edition.pdf
    • https://cdn.shopify.com/s/files/1/0437/8607/6309/files/bapazepojufober.pdf
    • https://cdn.shopify.com/s/files/1/0437/2011/4331/files/83948422032.pdf
    • https://cdn.shopify.com/s/files/1/0437/6159/8616/files/fundamental_of_stock_market.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_off00006805.bin
a9eab3deb57873d4b9d900d6b29416e649504ece082be44aa509a96158a879e2
pdf-font-stream PDF embedded font (sfnt) at offset 0x6805 5444 bytes
font_01_sfnt_off00007a83.bin
b47964b1db78f6b6a7de5fe46c755ab7379b6c441f3372f7ad695e25c340c15f
pdf-font-stream PDF embedded font (sfnt) at offset 0x7A83 10104 bytes