Malicious PDF — malware analysis report

Static analysis result for SHA-256 e4ae4920ffd1e04e…

MALICIOUS

PDF

91.1 KB Created: 2020-07-25 18:58:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: e1167a2ba63b0a238dd239533552804c SHA-1: 1fba4f1760dbe48e7fe6c4aefcce1d3235458dc0 SHA-256: e4ae4920ffd1e04ebe710506876fda877596eb8a159c76d9b2646fa88aa138c0
154 Risk Score

Malware Insights

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

The PDF file contains embedded links, with one pointing to a known malicious redirector. The document body, though heavily obfuscated, suggests a lure related to 'Krusty krab theme flute sheet music'. The presence of numerous external PDF links further indicates a link farm or redirection strategy. The ML classifier strongly flagged this PDF as malicious.

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/pify?keyword=krusty+krab+theme+flute+sheet+music
    • http://files.eusebiachurch.com/uploads/1/3/1/6/131636855/7678664.pdf
    • http://files.nickelcityaussies.com/uploads/1/3/1/0/131070912/f52f51.pdf
    • http://files.endymienne.com/uploads/1/3/1/4/131437523/8382578c.pdf
    • http://files.crownlifeseminars.com/uploads/1/3/2/7/132710669/fizezad-ronux.pdf
    • http://files.aerocustoms.com/uploads/1/3/1/3/131383247/8ad2f3b610b.pdf
    • https://cdn.shopify.com/s/files/1/0429/5802/8959/files/tijejakanegex.pdf
    • https://cdn.shopify.com/s/files/1/0432/0428/0481/files/savoliwowi.pdf
    • https://cdn.shopify.com/s/files/1/0427/8432/5798/files/gawafegujogejob.pdf
    • https://cdn.shopify.com/s/files/1/0430/9542/5191/files/58394549262.pdf
    • https://cdn.shopify.com/s/files/1/0434/8290/6789/files/48639245472.pdf
    • https://cdn.shopify.com/s/files/1/0435/0446/8134/files/90147402110.pdf
    • https://cdn.shopify.com/s/files/1/0437/0753/1432/files/60268402288.pdf
    • https://cdn.shopify.com/s/files/1/0428/8777/4367/files/wifaranadirijedixozejamu.pdf
    • https://cdn.shopify.com/s/files/1/0439/4775/3640/files/46642099364.pdf
    • https://cdn.shopify.com/s/files/1/0433/9990/5429/files/84712095246.pdf
    • https://cdn.shopify.com/s/files/1/0430/1137/5267/files/40633131135.pdf
    • https://cdn.shopify.com/s/files/1/0433/1218/5499/files/20474615007.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_off000128ab.bin
7f469e3523777448036d7952c4da08bc11e3f5f0fa0d722cbff08c855c38393b
pdf-font-stream PDF embedded font (sfnt) at offset 0x128AB 5064 bytes
font_01_sfnt_off000139e9.bin
cffb9bcbf1f2d5b3ac176955da96fe407276e31b24711e9691b73498e7fd1fb9
pdf-font-stream PDF embedded font (sfnt) at offset 0x139E9 10856 bytes