Malicious PDF — malware analysis report

Static analysis result for SHA-256 59e716c8e2eb0fd9…

MALICIOUS

PDF

52.7 KB Created: 2020-08-29 20:48:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: d288cb4dbfc16ef5db565ef6356643b3 SHA-1: 23d5788ec59b8180b7375535b61053f79a2cbbe2 SHA-256: 59e716c8e2eb0fd95e0fc6eb674defccace71c071db591bf9d29bf9f9b89d545
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, which is also present in the document body. This link, 'https://ttraff.link/wix?keyword=bitvise+ssh+client+for+windows+7', likely leads to a malicious site. The PDF also exhibits characteristics of a link farm, with numerous embedded URLs pointing to various PDF files, suggesting an attempt to manipulate search engine results or distribute further content. The ML classifier strongly supports the malicious nature of this PDF.

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.link/wix?keyword=bitvise+ssh+client+for+windows+7
    • https://cdn.shopify.com/s/files/1/0429/4157/9420/files/38052782784.pdf
    • https://cdn.shopify.com/s/files/1/0434/5767/5431/files/introduction_to_machine_learning_with_python_o_reilly.pdf
    • https://cdn.shopify.com/s/files/1/0433/2562/0374/files/belefolifuxip.pdf
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/28391359898.pdf
    • https://cdn.shopify.com/s/files/1/0440/3753/7942/files/19995544329.pdf
    • https://static.usrfiles.com/ugd/b8c837_1cb4107600054da8b5f169b8a7abdea4.pdf
    • https://static.usrfiles.com/ugd/b88e3d_3fd8ced6d10c4010b5aa2fd11b021743.pdf
    • https://static.usrfiles.com/ugd/c1615c_e7d67452b0564098a116f7fc863a716e.pdf
    • https://static.usrfiles.com/ugd/accd1f_9f3ad741234944528e22eecba0208421.pdf
    • https://static.usrfiles.com/ugd/b8c837_63247470740942c4ba67028261931cfb.pdf
    • https://static.usrfiles.com/ugd/b8c837_acae9f8603aa45ad8ee2cd57f7623b9f.pdf
    • https://static.usrfiles.com/ugd/b47706_685932e483ab467fb4bf4e072bd1c588.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_off0000891c.bin
85b42783083d9d3f94f31be6f1b8fad64e2b452e2df1b0b7c5fbd774c2888d71
pdf-font-stream PDF embedded font (sfnt) at offset 0x891C 5180 bytes
font_01_sfnt_off00009ace.bin
2e2d5feb7bba40d4e5c16fbcffb54562c5f91a17260049e4e2b8b8ceb486e382
pdf-font-stream PDF embedded font (sfnt) at offset 0x9ACE 13420 bytes