Malicious PDF — malware analysis report

Static analysis result for SHA-256 f3f1ec79b15e3a9b…

MALICIOUS

PDF

65.5 KB Created: 2020-08-01 01:29:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: f304f0ac5ccfdd717da7f498abafa8aa SHA-1: 1fb25c2ba21920079cf661c3bd2dfe2904d604c7 SHA-256: f3f1ec79b15e3a9bcd30d9acb3f9dcc884a6a11ab34ea29fde37c5a86955b228
152 Risk Score

Malware Insights

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

The PDF contains a mass of external links, many hosted on Shopify, designed to create a link farm. One of these links, https://ttraff.cc/pify?keyword=huffman+coding+example, is identified as a malicious redirector. The document body, though heavily obfuscated, contains the same URL, suggesting it's the primary lure. 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.cc/pify?keyword=huffman+coding+example
    • http://files.midatlanticbrassbandfestival.com/uploads/1/3/0/7/130775557/230140.pdf
    • http://files.bulubulup.com/uploads/1/3/1/3/131398428/kunomifubupesodufagi.pdf
    • http://files.helenhalliday.com/uploads/1/3/1/3/131379266/5801697.pdf
    • https://cdn.shopify.com/s/files/1/0429/0864/7580/files/kekelejujowewatu.pdf
    • https://cdn.shopify.com/s/files/1/0433/9102/5306/files/kadavexebegezugoxufoga.pdf
    • https://cdn.shopify.com/s/files/1/0431/8858/4605/files/31492922879.pdf
    • https://cdn.shopify.com/s/files/1/0427/4916/5734/files/42836141016.pdf
    • https://cdn.shopify.com/s/files/1/0437/3299/2161/files/gezuluwopokaduru.pdf
    • https://cdn.shopify.com/s/files/1/0429/6320/6307/files/87939073689.pdf
    • https://cdn.shopify.com/s/files/1/0432/3685/1874/files/defifajopariritu.pdf
    • https://cdn.shopify.com/s/files/1/0432/1270/1854/files/57060323724.pdf
    • https://cdn.shopify.com/s/files/1/0433/2807/7992/files/fiwefirasalifux.pdf
    • https://cdn.shopify.com/s/files/1/0433/6680/9765/files/mekonozakagorugamegituxuk.pdf
    • https://cdn.shopify.com/s/files/1/0429/2699/7663/files/nomuwozoluwapitip.pdf
    • https://cdn.shopify.com/s/files/1/0438/5911/6182/files/xovefokegifomajewiti.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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000a472.bin
95cb4d3abb15377ba6343303abaea7f5b8a23a62aee1d3e215442f5b15fc3992
pdf-font-stream PDF embedded font (sfnt) at offset 0xA472 5228 bytes
font_01_sfnt_off0000b632.bin
e1f68cd51fe5aee9a4d5f8f9dffc40f51642c3d44017141c40215afa003a0c8b
pdf-font-stream PDF embedded font (sfnt) at offset 0xB632 14408 bytes
font_02_sfnt_off0000e39f.bin
b40e0d0defe972582ad7e739fc4d795bb6a3f7e00f71b5f1de95c03cb5bfb272
pdf-font-stream PDF embedded font (sfnt) at offset 0xE39F 16148 bytes