Malicious PDF — malware analysis report

Static analysis result for SHA-256 825d2e5c31367d32…

MALICIOUS

PDF

49.8 KB Created: 2020-07-30 01:13:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 9da1f2644a8d7c8a59587346ffbf550c SHA-1: a309512e44724a57da1cfbc88b5d7d7bc331c25e SHA-256: 825d2e5c31367d32fec4e31d6354e5b76ecb93a643488b0776b324b3533e8e9b
154 Risk Score

Malware Insights

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

The PDF contains a large number of embedded links, many of which point to a link farm designed to manipulate search engine results. One of the embedded URLs, 'https://ttraff.ru/pify?keyword=simple+algebra+equations+worksheet+pdf', is flagged as a known malicious redirector. The document's content is obfuscated, but the presence of numerous links and the malicious redirector strongly suggest an attempt to lure users to malicious sites, likely for further exploitation or phishing.

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=simple+algebra+equations+worksheet+pdf
    • http://files.hackingdermatology.org/uploads/1/3/1/6/131606465/0c6657d48a30a.pdf
    • http://files.chisagocountyfair.org/uploads/1/3/1/3/131379183/4eb7298c8b.pdf
    • http://files.gaia-latableturquoise.com/uploads/1/3/0/8/130814070/fosepowikugerava.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://cdn.shopify.com/s/files/1/0433/5733/9813/files/voruduvedidanezebib.pdf
    • https://cdn.shopify.com/s/files/1/0429/8643/8807/files/40454992296.pdf
    • https://cdn.shopify.com/s/files/1/0429/5491/5993/files/woxunaz.pdf
    • https://cdn.shopify.com/s/files/1/0429/5131/1513/files/welefobajoxajatepafa.pdf
    • https://cdn.shopify.com/s/files/1/0430/6881/7562/files/80802617450.pdf
    • https://cdn.shopify.com/s/files/1/0434/0157/6604/files/rotejitarutirojitemumuzu.pdf
    • https://cdn.shopify.com/s/files/1/0432/3239/5426/files/20311744406.pdf
    • https://cdn.shopify.com/s/files/1/0431/7046/3895/files/libopu.pdf
    • https://cdn.shopify.com/s/files/1/0428/8105/6935/files/52103405556.pdf
    • https://cdn.shopify.com/s/files/1/0433/2231/0811/files/37853171810.pdf
    • https://cdn.shopify.com/s/files/1/0437/0323/8811/files/23647885116.pdf
    • https://cdn.shopify.com/s/files/1/0433/6363/1272/files/66570083503.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_off000082a7.bin
fb2cd7b8f20804b762e0c697aeb18166cacbd7507f258cc31be4b102896eccbd
pdf-font-stream PDF embedded font (sfnt) at offset 0x82A7 5860 bytes
font_01_sfnt_off00009665.bin
f4bc3d888fb7b88b56f5cc01c28faf8c75d5cd910c34614dc16b2a8dd1a0882d
pdf-font-stream PDF embedded font (sfnt) at offset 0x9665 10308 bytes