Malicious PDF — malware analysis report

Static analysis result for SHA-256 051eefb9cc3bca0f…

MALICIOUS

PDF

48.4 KB Created: 2020-08-29 15:10:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 9b5d48f11060d963d6692b6dc7804362 SHA-1: 1843162ad8bc90ef5419a348353229b12c451885 SHA-256: 051eefb9cc3bca0fc84008958a748b5054145102b34f41a2696d1e10c78de8b2
154 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a heuristic firing for linking to known malicious redirector infrastructure, specifically the URL https://ttraff.cc/wix?keyword=c+programming+absolute+beginner+s+guide. Additionally, it exhibits characteristics of a PDF link farm, embedding numerous external PDF links, many of which are benign but serve to obscure the malicious intent. The ML classifier strongly flagged this PDF as malicious, supporting the conclusion that it is designed to redirect users to harmful content.

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.cc/wix?keyword=c+programming+absolute+beginner+s+guide
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://static.usrfiles.com/ugd/b8c837_254d8a0b7b6c44789f1ec6f834f21c83.pdf
    • https://static.usrfiles.com/ugd/b8c837_9757a9fd410f454e90d91bf7c36e36fc.pdf
    • https://static.usrfiles.com/ugd/b8c837_115d4c827926448d96e61df9fdccd4bb.pdf
    • https://static.usrfiles.com/ugd/b8c837_d8405a7a87514521a8b6e3a1fa891439.pdf
    • https://static.usrfiles.com/ugd/07625c_0902f4d2509d4c399a6d8862ffe48aef.pdf
    • https://cdn.shopify.com/s/files/1/0436/9720/9498/files/50597415445.pdf
    • https://cdn.shopify.com/s/files/1/0431/8507/8423/files/vepigovefozunijunari.pdf
    • https://cdn.shopify.com/s/files/1/0449/3164/5608/files/answer_paszcze_zimowe.pdf
    • https://cdn.shopify.com/s/files/1/0437/9531/6896/files/pigejinugaripuj.pdf
    • https://cdn.shopify.com/s/files/1/0439/2812/5595/files/minilugopeded.pdf
    • https://cdn.shopify.com/s/files/1/0433/9780/8279/files/rowumuzak.pdf
    • https://static.usrfiles.com/ugd/b8c837_ec91ed554d8b4c7890fbe5ab775b1a12.pdf
    • https://static.usrfiles.com/ugd/73cb9e_3e7d3319eb434d28ae05f2b084a5d004.pdf
    • https://static.usrfiles.com/ugd/e3ed1f_7858870b1eb443bda4b68b575a07f28a.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_off00008177.bin
7a82892cd558a9615023f85dcfcfe98949618bd751c563a7f37926367c24f9ac
pdf-font-stream PDF embedded font (sfnt) at offset 0x8177 5324 bytes
font_01_sfnt_off0000936c.bin
65d8408f26f197d2226aa6377d036af359f68104342b1b59f79db6dac2b83098
pdf-font-stream PDF embedded font (sfnt) at offset 0x936C 9752 bytes