Malicious PDF — malware analysis report

Static analysis result for SHA-256 af241c8212bda6e5…

MALICIOUS

PDF

40.4 KB Created: 2020-08-31 23:52:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 13f8173fa0734b20403ed4f5141f451b SHA-1: 46ce0670771e29a4d69280afcbae64e8f525ee14 SHA-256: af241c8212bda6e5fd0635b90f03ad9ce41f79abad146e8a64df91fe7381d10f
152 Risk Score

Malware Insights

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

The PDF contains a large number of embedded links, many of which point to external resources. One critical heuristic firing indicates that the PDF links to known malicious redirector infrastructure, specifically 'https://ttraff.me/wix?keyword=assets+held+for+sale+balance+sheet+classification'. The ML classifier also strongly flagged this PDF as malicious. The document body, though partially corrupted, contains text related to financial assets and the authoring application 'wkhtmltopdf', suggesting a lure to disguise the malicious links.

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.me/wix?keyword=assets+held+for+sale+balance+sheet+classification
    • https://static.usrfiles.com/ugd/b8c837_893b824729e540a7a7df4385467bf7b6.pdf
    • https://static.usrfiles.com/ugd/12f4eb_615d886f5b864794836d14322ee64246.pdf
    • https://static.usrfiles.com/ugd/b8c837_7e9a4332909842f7ad06228ba793f6b9.pdf
    • https://cdn.shopify.com/s/files/1/0428/1437/4047/files/migabifepek.pdf
    • https://cdn.shopify.com/s/files/1/0440/6158/9669/files/nuruxegularugagidu.pdf
    • https://cdn.shopify.com/s/files/1/0430/4093/1991/files/xigilu.pdf
    • https://cdn.shopify.com/s/files/1/0459/9824/3999/files/digital_electronics_book.pdf
    • https://static.usrfiles.com/ugd/bae363_321599981bc34ba1aaebc40bc1008f32.pdf
    • https://static.usrfiles.com/ugd/b8c837_576b572585034db998e9fea34c285dc0.pdf
    • https://static.usrfiles.com/ugd/b8c837_98f4388ee5e94d30af131694b62b071d.pdf
    • https://static.usrfiles.com/ugd/724fb5_3fdb29a5cea44801901651b561211c6f.pdf
    • https://static.usrfiles.com/ugd/4cf28d_40626d773f5b447c8b60ab815d3b8c93.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_off0000606c.bin
bba4f72b0b855c40aafca4a56c9b8b2e1febd9b90ac7a33f6ffdce518463ee3c
pdf-font-stream PDF embedded font (sfnt) at offset 0x606C 5236 bytes
font_01_sfnt_off00007237.bin
c90612efb8de5d13914a97b2982eea15e679b05e9c8e7586f374617f0dfd0025
pdf-font-stream PDF embedded font (sfnt) at offset 0x7237 10228 bytes