Malicious PDF — malware analysis report

Static analysis result for SHA-256 8cfe8e6a0892627d…

MALICIOUS

PDF

43.5 KB Created: 2020-08-22 15:15:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: f61e8c93c24e7c6ce3ee0dccd30ac8b9 SHA-1: 9e2d3640c5bb87896f50965505c49d95db8e9425 SHA-256: 8cfe8e6a0892627d975650367f711aaaa929cd20983a04bf41de2c619b5256d7
152 Risk Score

Malware Insights

MITRE ATT&CK
T1566.002 Spearphishing Attachment T1059.001 PowerShell

The PDF contains numerous embedded links, with a critical heuristic firing for a malicious redirector. The document body, though heavily obfuscated, contains text suggesting a lure related to 'world history book pdf 9th grade' and includes the malicious URL. The ML classifier also strongly indicated maliciousness. The primary attack vector appears to be social engineering via a deceptive link within the 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.cc/pify?keyword=world+history+book+pdf+9th+grade
    • http://files.samuel-evans.co.uk/uploads/1/3/2/7/132740499/nigojomidibez.pdf
    • http://wibevire.gillilandhcwildrags.com/uploads/1/3/0/7/130775407/lipetu_mepinu_bebisifuzegivev.pdf
    • https://cdn.shopify.com/s/files/1/0429/5000/0791/files/popolimugali.pdf
    • https://cdn.shopify.com/s/files/1/0429/8306/3715/files/kemex.pdf
    • https://cdn.shopify.com/s/files/1/0434/4355/2416/files/60352317545.pdf
    • https://cdn.shopify.com/s/files/1/0454/8689/9350/files/ashby_materials.pdf
    • https://cdn.shopify.com/s/files/1/0434/0655/7340/files/90626026364.pdf
    • https://cdn.shopify.com/s/files/1/0429/7133/2767/files/zizexuluguxelopoxonanal.pdf
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/norojakibi.pdf
    • https://cdn.shopify.com/s/files/1/0457/6591/8884/files/learning_head_to_tail_vector_addition_worksheet.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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00005a2c.bin
e0795c940b0ed2eded273b02c4b3834071f9e936d8f344c6cbc639e9ad9c908d
pdf-font-stream PDF embedded font (sfnt) at offset 0x5A2C 5460 bytes
font_01_sfnt_off00006ce6.bin
e512b29c5ce899ad72da8d396460120970a453ecf577f9371969c196bf54935e
pdf-font-stream PDF embedded font (sfnt) at offset 0x6CE6 11224 bytes
font_02_sfnt_off00009338.bin
a542ec26cea93e049a2e27cd59b1347dd9bbdea13775fd7b822b3c2b3136116f
pdf-font-stream PDF embedded font (sfnt) at offset 0x9338 4324 bytes