Malicious PDF — malware analysis report

Static analysis result for SHA-256 7fef452424c0b34a…

MALICIOUS

PDF

40.2 KB Created: 2020-10-30 12:52:46 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-27
MD5: 8d9b79f7d7165eeaab2bdd6e04458571 SHA-1: 739705329f5a83a0642f3e5c1633ac201cc7fb86 SHA-256: 7fef452424c0b34a2acfce58f5e825f70413cb4e7cfb0396ff8139451e8fc6d6
94 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF contains a link to a known malicious redirector, disguised as a worksheet. The ML classifier also strongly indicated maliciousness. The embedded URL is likely intended to lead the user to a malicious site, potentially for further exploitation or credential harvesting. No scripts were extracted, but the presence of a malicious URL is sufficient evidence of malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 3

  • 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.
  • 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/123?keyword=solving+polynomial+inequalities+worksheet In PDF document text
    • https://cdn-cms.f-static.net/uploads/4379841/normal_5f8c5f65aad59.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4380680/normal_5f8ca6e6becd4.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4369923/normal_5f8cb0be6311d.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4403531/normal_5f92fcc4ac6ec.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://uploads.strikinglycdn.com/files/d65eedfe-e74b-47d6-bbb0-0806a7e793db/losimatujifupipatomimuvod.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/5089c499-dcb1-4741-a37e-8b0ba2872dea/jepudasijatodilo.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/630bea69-3dcb-499c-8480-af706a35268a/widovegiwurimarepazug.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/4d3992ce-3283-4f7a-8864-2eaa37ec4ed1/908796520.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/c8291030-17ed-45cd-80de-7199277c51fa/58787880027.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/4c341324-cab5-4e5d-9195-ec3e1cd820e9/dipewenozuvokopodopab.pdfIn PDF document text
    • https://s3.amazonaws.com/nalifij/rixefudakuxaxibigimigev.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/e9a939c8-deb9-4636-a905-9b2903eb884d/56010592056.pdfIn PDF document text
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00005e48.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x5E48 5780 bytes
SHA-256: 853521ea358e074707282ce0cae1c5281e51e604b50cd190f4a5c66fdd25f7b3
font_01_sfnt_off000071e4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x71E4 9960 bytes
SHA-256: d1e5522c032252b322ae561ced00c03f03283d7abbfc27aa9ce7cd955b74c138