Malicious PDF — malware analysis report

Static analysis result for SHA-256 95157d76fa3b1b8b…

MALICIOUS

PDF

42.1 KB Created: 2020-08-25 12:26:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 166ec7dfaa1b7a268c73e7b4d81ca043 SHA-1: 3dc4c92820236ea21e7ea293bc6edd36d84ceafb SHA-256: 95157d76fa3b1b8b361fd2a5876b7b026ac0f01e5e5b03e95049d014c3a387c6
154 Risk Score

Malware Insights

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

The PDF contains a mass of external links, with one specifically pointing to a known malicious redirector. The document body, though heavily obfuscated, contains the URL 'https://ttraff.ru/pify?keyword=writing+exponential+functions+practice+worksheet', which is also listed as a malicious redirector. This suggests the primary goal is to redirect the user to malicious infrastructure.

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=writing+exponential+functions+practice+worksheet
    • http://files.mapleafdals.com/uploads/1/3/1/4/131483184/feropoveka.pdf
    • http://rezuwevaf.myorianstudio.com/uploads/1/3/1/4/131408027/wegojikinotu.pdf
    • https://cdn.shopify.com/s/files/1/0427/9864/5404/files/21249309668.pdf
    • https://cdn.shopify.com/s/files/1/0437/4246/2106/files/demigirolorowininidibe.pdf
    • https://cdn.shopify.com/s/files/1/0432/3983/3755/files/apache_cassandra_documentation.pdf
    • https://cdn.shopify.com/s/files/1/0465/3986/6270/files/54287040473.pdf
    • https://cdn.shopify.com/s/files/1/0434/3804/7384/files/android_pie_font_magisk_module.pdf
    • https://cdn.shopify.com/s/files/1/0431/1266/1152/files/levuz.pdf
    • https://cdn.shopify.com/s/files/1/0430/5158/1597/files/fanuposabenugapotevisoda.pdf
    • https://cdn.shopify.com/s/files/1/0440/6280/2085/files/lowuwizufupoxokidomu.pdf
    • https://cdn.shopify.com/s/files/1/0434/3057/6285/files/fosugirofigebe.pdf
    • https://cdn.shopify.com/s/files/1/0430/8657/7828/files/laxafurokinev.pdf
    • https://cdn.shopify.com/s/files/1/0435/6790/6977/files/badosagamiwivavunapu.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_off000064a2.bin
6c3120439da93e6b5d0cfdd741c4d2663795bf3fc943870ca9e2bd4531cf5d5d
pdf-font-stream PDF embedded font (sfnt) at offset 0x64A2 5516 bytes
font_01_sfnt_off0000777a.bin
2f2cce153f31fc77cab8d8c4003c0258e012063c7ac5d4505cd2891f3c7f671c
pdf-font-stream PDF embedded font (sfnt) at offset 0x777A 10364 bytes