Malicious PDF — malware analysis report

Static analysis result for SHA-256 771ae7b0d93158b2…

MALICIOUS

PDF

45.9 KB Created: 2020-08-18 22:01:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: da6adf0bc2114319836a2f0a9d168aec SHA-1: 55c12550c80ff80182ebf55ebc7e5d5b455ba093 SHA-256: 771ae7b0d93158b2f0063c85615a4dd0fc1af7430af058fb81ff318921dca08b
154 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a link to a known malicious redirector, suggesting an attempt to lead the user to malicious content. The document body, though heavily obfuscated, contains references to 'fieldrunners attack guide' and numerous URLs, many of which point to Shopify domains hosting other PDFs, potentially as part of a link farm or SEO manipulation to obscure the malicious intent. 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/pify?keyword=fieldrunners+attack+guide
    • http://files.musicin233.com/uploads/1/3/2/7/132740905/20eb0d2.pdf
    • http://teguboz.arnaldomorales.com/uploads/1/3/1/6/131607095/a89010.pdf
    • http://kijogon.socalroofingpros.net/uploads/1/3/2/7/132740494/6ae91d.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://cdn.shopify.com/s/files/1/0433/9813/5966/files/17911094902.pdf
    • https://cdn.shopify.com/s/files/1/0431/5637/3659/files/83257841410.pdf
    • https://cdn.shopify.com/s/files/1/0447/8353/4229/files/aeneid_virgil_english.pdf
    • https://cdn.shopify.com/s/files/1/0436/9013/1609/files/bee_venom_collector_pdf.pdf
    • https://cdn.shopify.com/s/files/1/0435/6934/8763/files/tapozabolokesubune.pdf
    • https://cdn.shopify.com/s/files/1/0428/3164/2780/files/91178447309.pdf
    • https://cdn.shopify.com/s/files/1/0433/9728/3996/files/bibutimadu.pdf
    • https://cdn.shopify.com/s/files/1/0432/4163/5997/files/68399641086.pdf
    • https://cdn.shopify.com/s/files/1/0427/5562/1031/files/5378026295.pdf
    • https://cdn.shopify.com/s/files/1/0436/4389/5958/files/16360155007.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_off00007701.bin
16268a66ff69a0f32dfd95c5159ef82faabd066482084e9cffbc035fef795313
pdf-font-stream PDF embedded font (sfnt) at offset 0x7701 5128 bytes
font_01_sfnt_off00008876.bin
4e68256db679a2075237d035741d52d1422d8b031bb3e9986a94209a69aba6e5
pdf-font-stream PDF embedded font (sfnt) at offset 0x8876 10120 bytes