Malicious PDF — malware analysis report

Static analysis result for SHA-256 824c037213b6fcdd…

MALICIOUS

PDF

38.6 KB Created: 2020-08-14 19:31:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 8a484e12ebc85b27e828b196a9e4a810 SHA-1: 7ea778aa010fc1c9d14074daa0db34e53ae8df80 SHA-256: 824c037213b6fcdde58ddb5f07262464702623841440bdefd837ca36f6100f7c
154 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a large number of embedded links, many of which point to external websites, including a known malicious redirector. The document body, though obfuscated, contains a URL that appears to be part of a link farm strategy, likely intended to drive traffic to malicious sites. 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/wb?keyword=vmware%20nsx%20architecture%20pdf
    • http://files.aulac-restaurant.com.au/uploads/1/3/1/3/131379194/ginuw.pdf
    • http://files.longcreekschool.com/uploads/1/3/1/4/131406036/8237860.pdf
    • http://files.saratogatemple.org/uploads/1/3/0/7/130738921/fec4887849a22.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://cdn.shopify.com/s/files/1/0431/6043/6896/files/86928561977.pdf
    • https://cdn.shopify.com/s/files/1/0428/6945/7063/files/3409291687.pdf
    • https://cdn.shopify.com/s/files/1/0437/4839/3112/files/discord_overlay_not_working_wow.pdf
    • https://cdn.shopify.com/s/files/1/0444/4746/5639/files/jobepolabotuvebufo.pdf
    • https://cdn.shopify.com/s/files/1/0433/7926/1590/files/luzuzavifagefudebimiwelol.pdf
    • https://cdn.shopify.com/s/files/1/0433/9033/7189/files/68538237548.pdf
    • https://cdn.shopify.com/s/files/1/0434/4433/8838/files/logical_reasoning_questions_and_answers_in_marathi.pdf
    • https://cdn.shopify.com/s/files/1/0433/3256/7195/files/48416041790.pdf
    • https://cdn.shopify.com/s/files/1/0450/0701/2004/files/automobilismo_d_epoca_download.pdf
    • https://cdn.shopify.com/s/files/1/0430/1045/7753/files/tipewikawonezeki.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/
    • http://scripts.sil.org/OFL

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00005a20.bin
8592c92ebad5d1fd3985b599e6a3c127f46073b4c0c02f041daa23ffaf3b9c6f
pdf-font-stream PDF embedded font (sfnt) at offset 0x5A20 5488 bytes
font_01_sfnt_off00006ca5.bin
e5ab18a7a1482bf8bdfb66e8d904d3d33b99906913d8c3e15d2bc00ed34b3e5f
pdf-font-stream PDF embedded font (sfnt) at offset 0x6CA5 9804 bytes