Malicious PDF — malware analysis report

Static analysis result for SHA-256 aff4c712feef6bc0…

MALICIOUS

PDF

44.8 KB Created: 2020-08-30 19:21:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: ea5599863f3b7084366dc2092e6f4746 SHA-1: 1207bde756009119a08c7c22792f235d61961302 SHA-256: aff4c712feef6bc08e0649d70ae05c29499c31921c4d1b5f51b0e2a8e5516365
154 Risk Score

Malware Insights

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

The PDF file contains a heuristic firing for a malicious redirector link, pointing to 'ttraff.ru'. The document body, though heavily obfuscated, also contains this URL and references to sheet music, suggesting a lure. The file also exhibits characteristics of a link farm, with numerous embedded URLs pointing to external PDF documents, likely for SEO poisoning or to host further malicious content. The ML classifier strongly indicates maliciousness.

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/wix?keyword=turkish+march+sheet+music+beethoven
    • https://static.usrfiles.com/ugd/902d29_01c87a77cfb946cfb50c7ecc9c319097.pdf
    • https://static.usrfiles.com/ugd/ce0e6d_3cee01f1cc1249c6953b22e54b3e3bdf.pdf
    • https://static.usrfiles.com/ugd/99a8f2_0207ebc27cd34aa1a1283e22a4692883.pdf
    • https://static.usrfiles.com/ugd/b8c837_d43729fe8a844fb998c967e8a585d748.pdf
    • https://static.usrfiles.com/ugd/c3548c_780f2a81acc74d9996165088ed21faf0.pdf
    • https://cdn.shopify.com/s/files/1/0429/2696/4903/files/20262094914.pdf
    • https://cdn.shopify.com/s/files/1/0431/0378/1015/files/wamuvaxuxax.pdf
    • https://cdn.shopify.com/s/files/1/0434/4119/3110/files/88415784683.pdf
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/1317992411.pdf
    • https://cdn.shopify.com/s/files/1/0432/3573/7755/files/16480672363.pdf
    • https://cdn.shopify.com/s/files/1/0465/1584/7326/files/bibliography_mla_format_word.pdf
    • https://cdn.shopify.com/s/files/1/0430/6678/5949/files/zevukagosozufidodoj.pdf
    • https://static.usrfiles.com/ugd/696b8a_5ffec19e353742da81f013e1ccc6f7de.pdf
    • https://static.usrfiles.com/ugd/565485_48008b76cfb849e0a0ae2d11bd003c99.pdf
    • https://static.usrfiles.com/ugd/a4d998_688c200608e0403493b8ed134ae0cf5e.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_off00006157.bin
fbb5e6827f60a55f9b8165c37da9d8e311a8ac5b98b24dd244d783d8eed2286b
pdf-font-stream PDF embedded font (sfnt) at offset 0x6157 5220 bytes
font_01_sfnt_off000072ef.bin
a5b9ce10d846808a1f8bfd6ac0ab17ecd4e58353c162c6364c8a8c766326c73d
pdf-font-stream PDF embedded font (sfnt) at offset 0x72EF 15432 bytes