Malicious PDF — malware analysis report

Static analysis result for SHA-256 d758a9fb7019f9bc…

MALICIOUS

PDF

39.8 KB Created: 2020-08-28 01:30:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 2e9191d9bc9f0e4db53141f7af2259c9 SHA-1: ddd522714a94f7e5765032dd71c5fa8184d60121 SHA-256: d758a9fb7019f9bc4e7c951f0b4c3c9f25638c356326d9fc0b3c89e79f83a3fc
152 Risk Score

Malware Insights

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

The PDF contains numerous embedded links, with a critical heuristic identifying a link to a known malicious redirector. The document body, though partially corrupted, contains text related to 'chemistry textbook answers' and includes the malicious URL, suggesting a lure to a phishing or malware distribution site. The ML classifier strongly indicates maliciousness. No scripts were extracted, but the PDF structure and embedded links are sufficient to infer a malicious redirection attempt.

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.ru/pify?keyword=chemistry+textbook+answers+prentice
    • http://wivetudu.fusedfinery.com/uploads/1/3/0/7/130739163/3720d9877.pdf
    • https://cdn.shopify.com/s/files/1/0433/9528/5150/files/diccionario_ingles_espaol_larousse.pdf
    • https://cdn.shopify.com/s/files/1/0429/8244/1113/files/9958536629.pdf
    • https://cdn.shopify.com/s/files/1/0436/0483/6515/files/never_back_down_movie.pdf
    • https://cdn.shopify.com/s/files/1/0463/0754/1149/files/why_was_mueller_report_redacted.pdf
    • https://cdn.shopify.com/s/files/1/0430/3906/4225/files/download_nsfas_application_form_for_2020.pdf
    • https://cdn.shopify.com/s/files/1/0436/6699/7398/files/xejizotufogewabagebi.pdf
    • https://cdn.shopify.com/s/files/1/0432/0998/2107/files/zesegibupaxixabazupog.pdf
    • https://cdn.shopify.com/s/files/1/0438/4063/5042/files/14415684252.pdf
    • https://cdn.shopify.com/s/files/1/0431/9313/9364/files/lodusamupupukipamebito.pdf
    • https://cdn.shopify.com/s/files/1/0431/0243/7527/files/binekefowibiv.pdf
    • https://cdn.shopify.com/s/files/1/0430/8379/2533/files/aftas_bucales.pdf
    • https://cdn.shopify.com/s/files/1/0434/0767/1448/files/39056669338.pdf
    • https://cdn.shopify.com/s/files/1/0429/3849/9235/files/domifafoba.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_off00005351.bin
80099a6dad5cb5026b48dd3a7e3b0f81feb89225c7f39e44f29ac1b96f5595f8
pdf-font-stream PDF embedded font (sfnt) at offset 0x5351 5512 bytes
font_01_sfnt_off000065fa.bin
9d879075f2e597b58cbb182b260a3b9604c2b8d57d01aa59ef8a3bfbb31dffd0
pdf-font-stream PDF embedded font (sfnt) at offset 0x65FA 13412 bytes