Malicious PDF — malware analysis report

Static analysis result for SHA-256 8866f6c9a551af17…

MALICIOUS

PDF

39.2 KB Created: 2020-08-15 00:43:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 7da81cff1fe796dde4460412fdea4598 SHA-1: 290351e6662cf1bfd62e8afd0f99a9071d6027e5 SHA-256: 8866f6c9a551af170b15897f44891557f032cb9b5e96e9b1d7a7d378eba11f4f
154 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF contains numerous embedded links, with a critical heuristic identifying a link to a known malicious redirector. The document body, though partially corrupted, contains text suggesting it is disguised as educational material ('Arithmetic worksheets year 5'). The presence of embedded URLs and the ML classifier's high confidence score indicate a malicious intent to redirect users to harmful content.

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/wb?keyword=arithmetic%20worksheets%20year%205
    • http://gebofeva.reneparagas.com/uploads/1/3/0/8/130813077/winakow.pdf
    • http://files.mjohnson7.com/uploads/1/3/0/7/130739060/lerisutelizatetel.pdf
    • http://kisatoti.normanchildrenchorus.org/uploads/1/3/0/8/130813059/wogixirevali.pdf
    • http://gamukax.windwardtoeden.com/uploads/1/3/1/3/131383645/9746102.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://cdn.shopify.com/s/files/1/0435/4693/5451/files/28766624217.pdf
    • https://cdn.shopify.com/s/files/1/0436/3363/9584/files/tosusaw.pdf
    • https://cdn.shopify.com/s/files/1/0436/1817/3086/files/56098971062.pdf
    • https://cdn.shopify.com/s/files/1/0435/2868/3672/files/guzumonek.pdf
    • https://cdn.shopify.com/s/files/1/0429/8709/4177/files/gutimepij.pdf
    • https://cdn.shopify.com/s/files/1/0431/2875/0241/files/kuwamomojejuxazeduxeru.pdf
    • https://cdn.shopify.com/s/files/1/0432/6958/7104/files/povinediwabiwuwakas.pdf
    • https://cdn.shopify.com/s/files/1/0437/6032/0669/files/66997481755.pdf
    • https://cdn.shopify.com/s/files/1/0436/9186/8313/files/rename_multiple_files.pdf
    • https://cdn.shopify.com/s/files/1/0428/1116/2790/files/12974079290.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_off00005a84.bin
bcfbccc119b2f19381a5baafb29b1214e879350c6e8f294b0cf1c3bc5721d4bb
pdf-font-stream PDF embedded font (sfnt) at offset 0x5A84 5380 bytes
font_01_sfnt_off00006cbf.bin
9bea041404450db56623036f51cfe26d942e5995faafec9ca5117a0204e4ada6
pdf-font-stream PDF embedded font (sfnt) at offset 0x6CBF 10428 bytes