Malicious PDF — malware analysis report

Static analysis result for SHA-256 28c6dbfe7608f85b…

MALICIOUS

PDF

42.6 KB Created: 2020-08-11 02:55:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 146b86db02dadeea10b9480221b0b167 SHA-1: 586543801ffae5a5418a14b35ae89f6fa0cb7972 SHA-256: 28c6dbfe7608f85b6b1bc1bbc9b829af0bfe015cecc0fa65f250cef18899e145
152 Risk Score

Malware Insights

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

The PDF contains a critical heuristic firing for a malicious redirector link pointing to 'ttraff.com'. The document body, though heavily obfuscated, contains text related to 'mechanical reasoning test pdf free download' and the malicious URL. The PDF also exhibits characteristics of a link farm, with numerous embedded URLs, many pointing to Shopify domains, likely to improve search engine ranking and lure victims. 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.com/pify?keyword=mechanical+reasoning+test+pdf+free+download
    • http://fuvinobim.balboabayvbc.com/uploads/1/3/1/4/131482975/vefaxowake.pdf
    • http://files.the-well.net/uploads/1/3/2/7/132740275/635475.pdf
    • http://files.wintercup-sportklettern.org/uploads/1/3/2/7/132711947/826a3c346a0905.pdf
    • http://files.rotarypassport.net/uploads/1/3/0/9/130969065/fab5b95d89.pdf
    • https://cdn.shopify.com/s/files/1/0435/8720/7327/files/jimiwa.pdf
    • https://cdn.shopify.com/s/files/1/0429/1824/8601/files/gomeriw.pdf
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/xajubebajodefemun.pdf
    • https://cdn.shopify.com/s/files/1/0433/3853/0965/files/purajijadowez.pdf
    • https://cdn.shopify.com/s/files/1/0433/4593/6534/files/important_name_reactions_in_organic_chemistry_class_12_cbse.pdf
    • https://cdn.shopify.com/s/files/1/0434/2539/8945/files/concise_biology_class_10_icse_book.pdf
    • https://cdn.shopify.com/s/files/1/0435/8632/2593/files/assassin_s_apprentice_book_1.pdf
    • https://cdn.shopify.com/s/files/1/0433/8126/0440/files/53815603910.pdf
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/52299098946.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_off0000675a.bin
e6afc89f9b842acaa6d4e03b7ca7474ba27fc34bcdd6e6db557d5ac55a760e38
pdf-font-stream PDF embedded font (sfnt) at offset 0x675A 5512 bytes
font_01_sfnt_off00007a1d.bin
75752f498fc3264c0d164364d18a8618e390aac5a46e521f4a850bed472a641e
pdf-font-stream PDF embedded font (sfnt) at offset 0x7A1D 10432 bytes