Malicious PDF — malware analysis report

Static analysis result for SHA-256 ad6ac437d26fe87e…

MALICIOUS

PDF

54.0 KB Created: 2020-08-30 20:48:12 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 3375a106d8ca066bc9019ef11654861f SHA-1: 33e65584eebc67eb22b25cb99b65d98434a4d3d1 SHA-256: ad6ac437d26fe87ee008fafc10988b520ed0b9565021538eefc9528adb98ecf4
152 Risk Score

Malware Insights

MITRE ATT&CK
T1566.002 Spearphishing Attachment T1200 Hardware Addends T1059.001 PowerShell

The PDF contains a critical heuristic firing for a malicious redirector link, pointing to 'https://ttraff.cc/wix?keyword=educacion+para+la+salud+en+mexico'. Additionally, it exhibits characteristics of a PDF link farm, with numerous embedded URLs. The ML classifier strongly flagged this PDF as malicious. The document body, though heavily obfuscated, also contains the malicious redirector URL and several benign-looking URLs hosted on 'static.usrfiles.com', likely part of the link farm.

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.cc/wix?keyword=educacion+para+la+salud+en+mexico
    • https://static.usrfiles.com/ugd/80bfa9_be1f0a1b8c444c5e85d72c8ccb45305d.pdf
    • https://static.usrfiles.com/ugd/fb83f1_f9ac54d731504aac88c25de7d7e29aad.pdf
    • https://static.usrfiles.com/ugd/43d598_c241cc7dbb3f46edbed6af0455e12c9a.pdf
    • https://static.usrfiles.com/ugd/b8c837_41f77f6964174f279e88c00b328106d1.pdf
    • https://static.usrfiles.com/ugd/60933b_363fe9ad59e54e75b0f1210a7bb93bde.pdf
    • https://static.usrfiles.com/ugd/739437_85166eda5b5d4b268d2fda8b58147b76.pdf
    • https://static.usrfiles.com/ugd/b8c837_f9e1d09f19614707b9afe083cfef4409.pdf
    • https://static.usrfiles.com/ugd/ce0e6d_5ea927ac4bff44a086f68b511858d2c4.pdf
    • https://static.usrfiles.com/ugd/b8c837_db43475c013b4a038cbe994afa5ee37f.pdf
    • https://static.usrfiles.com/ugd/4b7290_eca0e41ad0684a56a776f2e4f0d8d5ab.pdf
    • https://cdn.shopify.com/s/files/1/0437/0654/8377/files/gefoduxizutixofafutuxi.pdf
    • https://cdn.shopify.com/s/files/1/0434/7356/7901/files/last_logged_on_user_registry.pdf
    • https://cdn.shopify.com/s/files/1/0440/3675/1525/files/pesapoxakafiwimamuko.pdf
    • https://cdn.shopify.com/s/files/1/0435/9494/0573/files/80911211507.pdf
    • https://cdn.shopify.com/s/files/1/0429/1824/8601/files/4745761317.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://creativecommons.org/licenses/by-
    • 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_off000092ec.bin
1557fbdafa1099dc02c40bf4c1ba7a97913d7bf3bb3b1405e1b1aef528f6d393
pdf-font-stream PDF embedded font (sfnt) at offset 0x92EC 5244 bytes
font_01_sfnt_off0000a4a4.bin
d72f5fb7f8202857a453537974f95e530c1fc864d9f1f34f90e22344743b39aa
pdf-font-stream PDF embedded font (sfnt) at offset 0xA4A4 11400 bytes