Malicious PDF — malware analysis report

Static analysis result for SHA-256 8251517f3117c4b9…

MALICIOUS

PDF

34.8 KB Created: 2020-09-01 22:56:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: d75b40f66b96b553a0a94355beae1b57 SHA-1: f2d4f96f1c3b54e8adbf9c32676c5d7667487153 SHA-256: 8251517f3117c4b9943719dfb1e534068cb4bfe250da2e9a40c480e1ae725491
154 Risk Score

Malware Insights

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

The PDF contains numerous links, including one pointing to a known malicious redirector. The document body, though heavily obfuscated, appears to contain keywords related to educational worksheets, suggesting a lure to disguise the malicious intent. The ML classifier strongly flagged this PDF as malicious, indicating a high likelihood of malicious activity.

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.club/wix?keyword=english+worksheets+comparative+and+superlative+adjectives
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://cdn.shopify.com/s/files/1/0433/4062/8120/files/7850588545.pdf
    • https://cdn.shopify.com/s/files/1/0431/7980/2782/files/nubaxev.pdf
    • https://cdn.shopify.com/s/files/1/0429/2732/5343/files/kelidarijewabiseduridire.pdf
    • https://static.usrfiles.com/ugd/1e8759_2d659628f49c4a36a9e9a22b47ac60af.pdf
    • https://static.usrfiles.com/ugd/b910ae_1fa5089f391e43b49a2d99e76d69cd0f.pdf
    • https://static.usrfiles.com/ugd/3de8a6_a24b6097cee3473eb0aa79c3038defb1.pdf
    • https://static.usrfiles.com/ugd/b8c837_7dc2931988214758ae7ed0004285d4b9.pdf
    • https://static.usrfiles.com/ugd/b88e3d_c2242df99bcf41f3891ecdf450a1ee83.pdf
    • https://cdn.shopify.com/s/files/1/0429/9263/1962/files/duped.pdf
    • https://cdn.shopify.com/s/files/1/0430/2353/2195/files/27713326935.pdf
    • https://cdn.shopify.com/s/files/1/0431/6528/6566/files/jevugipu.pdf
    • https://cdn.shopify.com/s/files/1/0429/8797/8913/files/30421986765.pdf
    • https://cdn.shopify.com/s/files/1/0428/6811/3574/files/ecotourism_definition.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_off00004a0e.bin
978f81aee64e79525cc9250de5b77ff2695fe5d3a93f9330c7cbc6c783098947
pdf-font-stream PDF embedded font (sfnt) at offset 0x4A0E 5736 bytes
font_01_sfnt_off00005d84.bin
ceb585511c3a0a83ec399bf003093955540b256e36c2a37b99cdaa251ef1ba05
pdf-font-stream PDF embedded font (sfnt) at offset 0x5D84 9656 bytes