Malicious PDF — malware analysis report

Static analysis result for SHA-256 51cbde08af973dc6…

MALICIOUS

PDF

52.4 KB Created: 2020-08-28 20:55:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 2c99b0a00b52cbe8fd007cc72a7ffdf6 SHA-1: cfd39d91b682b93416d0a02c2de5f15a068a08cc SHA-256: 51cbde08af973dc6655f16894998e5927786b6a6116f9beaa5f572841aba1871
154 Risk Score

Malware Insights

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

The PDF document exhibits characteristics of a link farm, with numerous embedded URLs. One of these URLs, 'https://ttraff.cc/wix?keyword=convince+them+in+90+seconds+pdf', is flagged as a known malicious redirector. The document body, though heavily obfuscated, contains this URL and references 'wkhtmltopdf', suggesting it was generated programmatically. The ML classifier also strongly indicated maliciousness.

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=convince+them+in+90+seconds+pdf
    • https://static.usrfiles.com/ugd/b8c837_5706dc71ac81497597232a735f013d13.pdf
    • https://static.usrfiles.com/ugd/b8c837_91bf990c28404a6b84c79293ed3236f0.pdf
    • https://static.usrfiles.com/ugd/b8c837_d17db36ffd7a4e5c8cbb7c4f97faa918.pdf
    • https://static.usrfiles.com/ugd/b8c837_2a603dc3220846d0981cb1715f1b9116.pdf
    • https://static.usrfiles.com/ugd/b8c837_92d19a79efe345d0bc8ffa3f4fb0913e.pdf
    • https://static.usrfiles.com/ugd/b8c837_aed81ba7b08a47d29e8023889db43d12.pdf
    • https://static.usrfiles.com/ugd/b8c837_65e00add5f7e4f819b732a07367ea238.pdf
    • https://static.usrfiles.com/ugd/b8c837_0b872d4978ec428f9c84fd9f251eb11b.pdf
    • https://static.usrfiles.com/ugd/b8c837_edaa6cb7a74a450c919441e89df33d72.pdf
    • https://static.usrfiles.com/ugd/b8c837_0c7359982ed24ee2baf6faef56330ab3.pdf
    • https://cdn.shopify.com/s/files/1/0437/4586/9985/files/kupenijenaxopu.pdf
    • https://cdn.shopify.com/s/files/1/0433/8316/0995/files/tourner_dans_le_vide_english.pdf
    • https://cdn.shopify.com/s/files/1/0431/1970/6273/files/96656646775.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_off0000857d.bin
331450cd9cfb0af35125901bbd8c934fff1c33eb489988c0deb96cf558d8956b
pdf-font-stream PDF embedded font (sfnt) at offset 0x857D 5320 bytes
font_01_sfnt_off0000976f.bin
df64388cf78f87ffdc6493223a7af0745c1c11a74b987b066b04ad77282df602
pdf-font-stream PDF embedded font (sfnt) at offset 0x976F 2024 bytes
font_02_sfnt_off0000a0ce.bin
669e744a840e2ed8a738bafc00ef9aa96403555dc3f13d0e520d42bc2055f0f2
pdf-font-stream PDF embedded font (sfnt) at offset 0xA0CE 10372 bytes