Malicious PDF — malware analysis report

Static analysis result for SHA-256 8cf6b34bec77baf0…

MALICIOUS

PDF

34.4 KB Created: 2020-08-18 16:24:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: fcd91a4b060f70b19b36875efb26d32a SHA-1: 0fd0b22d4ab22cea0fead6679e4dd422502b713c SHA-256: 8cf6b34bec77baf081b30135e6ba110369009e4225be6e0baac2458ab5d7a988
152 Risk Score

Malware Insights

MITRE ATT&CK
T1566.002 Phishing: Spearphishing Attachment T1059.001 Command and Scripting Interpreter: PowerShell

The PDF contains a link to a known malicious redirector, ttraff.ru, which is used in conjunction with a lure about 'Banchory academy uniform'. The document also exhibits characteristics of a link farm, with numerous embedded URLs pointing to external PDF files, many hosted on Shopify. The ML classifier strongly indicated maliciousness. No scripts were extracted, but the primary attack vector appears to be social engineering via a deceptive link.

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=banchory+academy+uniform
    • http://gojujiz.independentorganicservices.com/uploads/1/3/0/9/130969862/1c41ce.pdf
    • http://files.popiconsblog.com/uploads/1/3/1/3/131398059/sazuneve.pdf
    • http://malox.barbarafoxartstudio.com/uploads/1/3/0/9/130969918/591bbf543b7.pdf
    • http://files.sarahsayswrite.com/uploads/1/3/2/3/132303388/086fa06ffdf9f5.pdf
    • https://cdn.shopify.com/s/files/1/0431/4162/8072/files/rexoweranekoxe.pdf
    • https://cdn.shopify.com/s/files/1/0430/1389/8403/files/80832459932.pdf
    • https://cdn.shopify.com/s/files/1/0434/0878/5562/files/padosakafike.pdf
    • https://cdn.shopify.com/s/files/1/0427/5834/0774/files/69320363804.pdf
    • https://cdn.shopify.com/s/files/1/0434/2857/7447/files/sylvia_day_afterburn.pdf
    • https://cdn.shopify.com/s/files/1/0433/2634/1272/files/zimijenunotosuf.pdf
    • https://cdn.shopify.com/s/files/1/0435/3651/5224/files/organic_chemistry_equations.pdf
    • https://cdn.shopify.com/s/files/1/0430/3293/6605/files/vexamozi.pdf
    • https://cdn.shopify.com/s/files/1/0445/6205/5332/files/capitalismo_periferico_raul_prebisch.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_off00004a63.bin
4c33166a90fbcb0b97165a20da3e00470b61a0a6a667a61742453413c86a9ef2
pdf-font-stream PDF embedded font (sfnt) at offset 0x4A63 5204 bytes
font_01_sfnt_off00005be6.bin
4e44dc393744f483af2f16119e7d61b5500f6b07a009d69218832375a9711cd7
pdf-font-stream PDF embedded font (sfnt) at offset 0x5BE6 9720 bytes