Malicious PDF — malware analysis report

Static analysis result for SHA-256 e69b8cba263264f2…

MALICIOUS

PDF

44.6 KB Created: 2020-08-30 11:08:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: e30c5a76f01efdfe5c50ae1b0475df08 SHA-1: 2c5043afd786ac75d9ce3afd4844fc57c327ef49 SHA-256: e69b8cba263264f260b718bfe06f183d253ac3c788b35304379cf3422272d231
154 Risk Score

Malware Insights

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

The PDF contains numerous embedded links, with one pointing to a known malicious redirector. The document body, though heavily obfuscated, contains text related to 'probability mass function questions' and a URL that appears to be part of a link farm designed to manipulate search engine results. The ML classifier strongly flagged this PDF as malicious, indicating a high likelihood of malicious intent.

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/wix?keyword=probability+mass+function+questions
    • https://cdn.shopify.com/s/files/1/0433/4796/8149/files/kebubuguromikakezarobama.pdf
    • https://cdn.shopify.com/s/files/1/0430/3519/7602/files/7188260797.pdf
    • https://cdn.shopify.com/s/files/1/0432/5287/5424/files/buteyko_breathing_technique_for_asthma.pdf
    • https://cdn.shopify.com/s/files/1/0430/3595/1257/files/49346873645.pdf
    • https://cdn.shopify.com/s/files/1/0438/4161/8082/files/55182772133.pdf
    • https://cdn.shopify.com/s/files/1/0437/4495/2471/files/standard_deviation_python.pdf
    • https://cdn.shopify.com/s/files/1/0435/5109/6984/files/25265149522.pdf
    • https://static.usrfiles.com/ugd/b8c837_1a3a734cf46e429b9e3999b0607068bf.pdf
    • https://static.usrfiles.com/ugd/b8c837_1eb702da17994c0290abf58c1edf473f.pdf
    • https://static.usrfiles.com/ugd/2f3ac6_52ac41de56344bb780fae0dd0ead3101.pdf
    • https://static.usrfiles.com/ugd/74a852_62f1d3cf863d4644be5439f843bd252b.pdf
    • https://static.usrfiles.com/ugd/136d07_8e24859d66bd4df2b2eb443f8e7cfb73.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_off00006460.bin
e68c66b555504a545820601e85fa8ff5d130abedf9a76081d072a14584fe0ec6
pdf-font-stream PDF embedded font (sfnt) at offset 0x6460 5396 bytes
font_01_sfnt_off000076ac.bin
7e1f26b4b74f00825ce5929352b30ae722e2b0fe572d080b4b957f9604cdfa2a
pdf-font-stream PDF embedded font (sfnt) at offset 0x76AC 14896 bytes