Malicious PDF — malware analysis report

Static analysis result for SHA-256 84a491f8b0f0a4b2…

MALICIOUS

PDF

39.8 KB Created: 2020-09-03 04:02:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 37a2a9b32a1735805eb0699430a8ef91 SHA-1: 97129992b08e21e15631198945af1da17f8bd26d SHA-256: 84a491f8b0f0a4b2b5b0a9842edd9bbd5c7cde15d88e54d28dce3a99aac5f871
152 Risk Score

Malware Insights

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

The PDF contains a critical heuristic firing for a malicious redirector link, specifically pointing to 'https://ttraff.link/wix?keyword=hmrc+clearance+letter+template'. This URL is presented within the document's body, suggesting a social engineering lure related to HMRC clearance. The PDF also exhibits characteristics of a link farm, with numerous embedded links to external PDFs, many hosted on Shopify. The ML classifier strongly flagged this PDF as malicious. No scripts were extracted from this sample.

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.link/wix?keyword=hmrc+clearance+letter+template
    • https://cdn.shopify.com/s/files/1/0434/2949/4936/files/9428850305.pdf
    • https://cdn.shopify.com/s/files/1/0436/8223/4521/files/akron_children27_s_hospital_child_life_internship.pdf
    • https://cdn.shopify.com/s/files/1/0438/3352/4386/files/24271794386.pdf
    • https://cdn.shopify.com/s/files/1/0445/8522/2308/files/zozulagitivove.pdf
    • https://cdn.shopify.com/s/files/1/0429/2784/9639/files/84185186131.pdf
    • https://cdn.shopify.com/s/files/1/0432/8760/9497/files/matilijugazenoju.pdf
    • https://cdn.shopify.com/s/files/1/0436/0136/3107/files/abap_sap_certification_questions_answers.pdf
    • https://cdn.shopify.com/s/files/1/0440/7777/7061/files/3994402325.pdf
    • https://static.usrfiles.com/ugd/9a242c_b66c2d4c9063414ca7338645fb553f03.pdf
    • https://static.usrfiles.com/ugd/b8c837_2c72998f81a24045ab070bbb986368ff.pdf
    • https://static.usrfiles.com/ugd/4d400c_5b83b80659e9465ab182fcf3246f84f7.pdf
    • https://static.usrfiles.com/ugd/f8de3e_b46c7414b56d48c895ddbcfd2f946263.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_off00005efd.bin
ccac4ac7e92ae0e28c8699e16dadf26496fbc7532dae8aece7e18e0fe906caa6
pdf-font-stream PDF embedded font (sfnt) at offset 0x5EFD 4864 bytes
font_01_sfnt_off00006f6b.bin
97e1ad47c5075d3a00a09fcef5be28bd4c488a10cf46f0f076113e9d543c19ff
pdf-font-stream PDF embedded font (sfnt) at offset 0x6F6B 10584 bytes