Malicious PDF — malware analysis report

Static analysis result for SHA-256 d337141a926067f8…

MALICIOUS

PDF

37.9 KB Created: 2020-08-22 07:59:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: f39f7b0990cae8c39be4a9321357b651 SHA-1: 183b94d2232e7bb167e747a8399ba60e46c75c6d SHA-256: d337141a926067f88ee0fc4a5ff2d80891172251699eef2fb595a6e85ced2d9d
152 Risk Score

Malware Insights

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

The PDF contains numerous embedded links, a technique often used to create link farms for SEO manipulation or to redirect users to malicious sites. One such link points to a known malicious redirector. The document body, though heavily obfuscated, contains text related to 'invertebrates worksheet 3rd grade' and the malicious URL, suggesting a lure to disguise the malicious intent. 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=invertebrates+worksheet+3rd+grade
    • http://files.publishthevision.com/uploads/1/3/0/9/130969915/serilu.pdf
    • https://cdn.shopify.com/s/files/1/0431/6761/3087/files/17326442810.pdf
    • https://cdn.shopify.com/s/files/1/0430/7664/9121/files/buscar_informacion_de_un_iphone_por_imei.pdf
    • https://cdn.shopify.com/s/files/1/0431/4228/3432/files/mukefubegegije.pdf
    • https://cdn.shopify.com/s/files/1/0428/5900/4070/files/76499348017.pdf
    • https://cdn.shopify.com/s/files/1/0439/8029/2254/files/82847928779.pdf
    • https://cdn.shopify.com/s/files/1/0431/7652/5984/files/25049948739.pdf
    • https://cdn.shopify.com/s/files/1/0439/5083/3822/files/molotowo.pdf
    • https://cdn.shopify.com/s/files/1/0431/9746/4731/files/98840656883.pdf
    • https://cdn.shopify.com/s/files/1/0454/2077/3544/files/panasonic_ceiling_fan_catalogue.pdf
    • https://cdn.shopify.com/s/files/1/0438/4810/6134/files/asphalt_nitro_hack_version_apk_free.pdf
    • https://cdn.shopify.com/s/files/1/0433/9816/8727/files/95724403534.pdf
    • https://cdn.shopify.com/s/files/1/0431/3759/7591/files/rolosenujosinimazunipubu.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_off000054eb.bin
2bf33a0a73f781b05a4ca329304e1d0b0263905c1da4cf96e86064a75f4db4ed
pdf-font-stream PDF embedded font (sfnt) at offset 0x54EB 5512 bytes
font_01_sfnt_off000067af.bin
aa5a63ed98ae01cacc4f3650dc75e9e771ae85da38e0351df7684c16bb0d91b2
pdf-font-stream PDF embedded font (sfnt) at offset 0x67AF 10304 bytes