Malicious PDF — malware analysis report

Static analysis result for SHA-256 e8adb3e875c7d80f…

MALICIOUS

PDF

38.0 KB Created: 2020-08-29 20:16:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 1918e8e55b1521c95fc011decbb1c9e8 SHA-1: b47f89c36f5f3e9b9a32cad4254d3319cd779d89 SHA-256: e8adb3e875c7d80fb1ff859c289d91f04bd6e10542195caaf198462091f5fe3c
152 Risk Score

Malware Insights

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

The PDF was flagged as malicious by an ML classifier and contains a high density of embedded links, many pointing to Shopify-hosted PDFs. One URL, 'https://ttraff.com/wix?keyword=ejercicios+de+porcentajes+sexto+basico', is identified as a malicious redirector. The document body, though heavily obfuscated, contains this URL and other PDF links, suggesting a lure to external content, potentially for phishing or a scam. The presence of a malicious redirector is the primary indicator 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=ejercicios+de+porcentajes+sexto+basico
    • https://cdn.shopify.com/s/files/1/0431/2737/3990/files/os_grandes_economistas.pdf
    • https://cdn.shopify.com/s/files/1/0431/3009/3728/files/executive_summary_example_business_plan.pdf
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/30552771564.pdf
    • https://cdn.shopify.com/s/files/1/0433/6009/2309/files/9280008800.pdf
    • https://cdn.shopify.com/s/files/1/0428/0057/8723/files/creative_brief_for_logo_design.pdf
    • https://cdn.shopify.com/s/files/1/0434/5020/4316/files/figopubobugiluv.pdf
    • https://cdn.shopify.com/s/files/1/0444/4743/2871/files/785143044.pdf
    • https://static.usrfiles.com/ugd/b8c837_847600236a9d42ee85982da61d0b7367.pdf
    • https://static.usrfiles.com/ugd/b8c837_0112edbed89145b9be46dabcb3dd0050.pdf
    • https://static.usrfiles.com/ugd/b8c837_273db06355834ebeb9bc3451295e22a3.pdf
    • https://static.usrfiles.com/ugd/b8c837_48dfbe299e9a4f2b8cf9536bfa38540c.pdf
    • https://static.usrfiles.com/ugd/b8c837_d81b9089030945d886ddd7c35c0b34d2.pdf
    • https://static.usrfiles.com/ugd/b8c837_5feaceab535f40989b1c48f2273993c2.pdf
    • https://static.usrfiles.com/ugd/b8c837_1107cff6c33844f5a82bf5b9e8e08998.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_off0000540d.bin
cabcc2b7ba89ebfc3c575568fce099019a724f8f91d6a8899400a1d92d122329
pdf-font-stream PDF embedded font (sfnt) at offset 0x540D 5276 bytes
font_01_sfnt_off00006605.bin
34e0fb261001ec1057501da688ac44f5eb58b3b2186d32605170a70b010cd91f
pdf-font-stream PDF embedded font (sfnt) at offset 0x6605 11576 bytes