Malicious PDF — malware analysis report

Static analysis result for SHA-256 7cc6f58fc047e39c…

MALICIOUS

PDF

46.1 KB Created: 2020-08-21 09:30:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 5cbf160593195e6a8f2a0df2f5eda748 SHA-1: f356e598b04675c534309a650a21844c34162220 SHA-256: 7cc6f58fc047e39cce467a12d7f03c1bf304d61da88362285534e8f1b3a5be77
154 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded links, with one identified as a malicious redirector. The heuristic 'PDF_MALICIOUS_REDIRECTOR_LINK' indicates that the link at https://ttraff.ru/pify?keyword=letter+a+tracing+worksheets+pdf leads to known malicious infrastructure. The 'PDF_SEO_LINK_FARM' heuristic further suggests a large number of external PDF links, many of which are likely intended to lead users to malicious sites. The ML classifier also strongly flagged this PDF as malicious.

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=letter+a+tracing+worksheets+pdf
    • http://files.peacepresbyterian.org/uploads/1/3/0/7/130775143/6d926cda8.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://cdn.shopify.com/s/files/1/0429/6504/1311/files/livre_apprendre_le_piano.pdf
    • https://cdn.shopify.com/s/files/1/0431/2930/7293/files/37205068838.pdf
    • https://cdn.shopify.com/s/files/1/0428/4776/4636/files/3383612025.pdf
    • https://cdn.shopify.com/s/files/1/0435/5964/9429/files/free_printable_reading_comprehension_worksheets_8th_grade.pdf
    • https://cdn.shopify.com/s/files/1/0435/1596/9688/files/android_17_x_saiyan_reader.pdf
    • https://cdn.shopify.com/s/files/1/0431/4005/5208/files/english_speaking_full_course_download.pdf
    • https://cdn.shopify.com/s/files/1/0431/5339/1780/files/91508912474.pdf
    • https://cdn.shopify.com/s/files/1/0432/4206/1986/files/30573222188.pdf
    • https://cdn.shopify.com/s/files/1/0434/2510/4028/files/71325034572.pdf
    • https://cdn.shopify.com/s/files/1/0430/9532/6887/files/81880313415.pdf
    • https://cdn.shopify.com/s/files/1/0428/4976/3494/files/tenevimowote.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/
    • http://scripts.sil.org/OFL

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00007496.bin
0a7bf571822157c20c633b070f21056cb6499931ca7d56f9fae26de09be12b82
pdf-font-stream PDF embedded font (sfnt) at offset 0x7496 5480 bytes
font_01_sfnt_off0000874f.bin
6eedd4a174f250c4962b135f280126fe25efced974c8acc604888f0ae7c01615
pdf-font-stream PDF embedded font (sfnt) at offset 0x874F 10664 bytes