Malicious PDF — malware analysis report

Static analysis result for SHA-256 b66ee653f320b27d…

MALICIOUS

PDF

45.8 KB Created: 2020-09-18 15:42:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 240b73792d547cb7adec4f7c39a11b86 SHA-1: 5d37c396c4547b5516c97c28e6b0e983f4206623 SHA-256: b66ee653f320b27d1c53ee95f55f27cec932e9ed2033832de9fe74aeb5cc5231
154 Risk Score

Malware Insights

MITRE ATT&CK
T1566.002 Spearphishing Attachment T1059.001 PowerShell T1204.002 Malicious Link

The PDF contains a link farm designed to appear as educational material, specifically a 'grade 5 workbook pdf'. The primary malicious link, https://ttraff.link/pify?keyword=grade+5+workbook+pdf, is a known redirector to malicious infrastructure. The ML classifier strongly supports the malicious verdict. No scripts were extracted, but the document's structure and embedded links indicate a social engineering lure.

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/pify?keyword=grade+5+workbook+pdf
    • https://cdn.shopify.com/s/files/1/0437/7618/0376/files/85695179048.pdf
    • https://cdn.shopify.com/s/files/1/0429/2267/2284/files/63416990534.pdf
    • https://cdn.shopify.com/s/files/1/0427/8140/9436/files/7720775134.pdf
    • https://cdn.shopify.com/s/files/1/0462/4767/4007/files/d_d_evoker_guide.pdf
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/vuketunaxu.pdf
    • https://cdn.shopify.com/s/files/1/0429/0582/9532/files/zanisexetigibujanob.pdf
    • https://cdn.shopify.com/s/files/1/0430/6314/8695/files/genero_narrativo_guia.pdf
    • https://cdn.shopify.com/s/files/1/0433/2650/5128/files/2704554891.pdf
    • https://b68e8142-c64a-4a92-930f-9624e66ef545.filesusr.com/ugd/49be48_5150a2e269dd43ee84f3574832b31293.pdf?index=true
    • https://5e0a78cf-6466-44c6-8919-b9df982d2578.filesusr.com/ugd/97634b_b4338e9d025349e989db7df05a9e3957.pdf?index=true
    • https://cdn.shopify.com/s/files/1/0430/8205/5833/files/28480323004.pdf
    • https://cdn.shopify.com/s/files/1/0459/0452/7514/files/90194629067.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_off0000758b.bin
8527e270639d33c254732589bbbba163f98dd6b0f3d4041d00f9e63da642a5e3
pdf-font-stream PDF embedded font (sfnt) at offset 0x758B 5276 bytes
font_01_sfnt_off000087a9.bin
f6bb586e0cd742d7ce78e9660fa193b09d393fbbe65cdc63d7d9b6d6ec1e21e2
pdf-font-stream PDF embedded font (sfnt) at offset 0x87A9 10292 bytes