Malicious PDF — malware analysis report

Static analysis result for SHA-256 bca991ac9ba2c953…

MALICIOUS

PDF

51.7 KB Created: 2020-09-01 02:37:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 2e2d1d60cdeefbc9a0c78d55226c3f64 SHA-1: 9e1c206a2940d8a2fed44d0c61b0be1a2931f5db SHA-256: bca991ac9ba2c95387f0b46744305eec7bfb510e116b23c427b7b48637aa7dc7
152 Risk Score

Malware Insights

MITRE ATT&CK
T1566.002 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains numerous embedded links, with one specifically pointing to a known malicious redirector at 'https://ttraff.ru/wix?keyword=refracting+telescope+image+formation'. The document body, though heavily obfuscated, also contains this URL and other links to PDF files hosted on static.usrfiles.com, suggesting a link farm or SEO poisoning tactic. 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/wix?keyword=refracting+telescope+image+formation
    • https://static.usrfiles.com/ugd/3aca14_e4f2258fbe934f77a8a3e74a4cb821cb.pdf
    • https://static.usrfiles.com/ugd/dc8a8e_a04206c87e964f0db31e766c991d7e2c.pdf
    • https://static.usrfiles.com/ugd/b3bc21_3e71650bf9404ec3adb00ba38652529b.pdf
    • https://static.usrfiles.com/ugd/429b25_c9200883ae2f4892b14d79fe811a0f2c.pdf
    • https://static.usrfiles.com/ugd/b28561_4b534f5d10e5405e8dafba387e03ba80.pdf
    • https://static.usrfiles.com/ugd/b8c837_bc102151c145408da4fd1d363b2187d9.pdf
    • https://static.usrfiles.com/ugd/0cd3a8_81019b6da997456ca6a17dacc93d5250.pdf
    • https://static.usrfiles.com/ugd/9b7d8a_1c59cf02fea34e95b0266b60c6cd3a09.pdf
    • https://static.usrfiles.com/ugd/1df9ea_147e6193b65a42e0a0aa9bb23683dd7f.pdf
    • https://cdn.shopify.com/s/files/1/0440/6899/5224/files/blood_culture_test_report.pdf
    • https://cdn.shopify.com/s/files/1/0430/0292/1111/files/54958715090.pdf
    • https://static.usrfiles.com/ugd/48d9a1_e570323b31ad4fa98e43f3f78a691869.pdf
    • https://static.usrfiles.com/ugd/850f07_7ac67fd62da04b098c4b6338fb4096bb.pdf
    • https://static.usrfiles.com/ugd/963627_983ac0444b3b463b9ddd7f569872dc90.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_off00008d6f.bin
34f898ca108408c9dfef9916485b63e38bba7fa6b5f554c14fca897d84cee2a3
pdf-font-stream PDF embedded font (sfnt) at offset 0x8D6F 5340 bytes
font_01_sfnt_off00009f95.bin
83e39d344c1891326282354f1e368a55a4815ea19ef7067b17c3e5da4bdbc6da
pdf-font-stream PDF embedded font (sfnt) at offset 0x9F95 10156 bytes