Malicious PDF — malware analysis report

Static analysis result for SHA-256 231e2fbab77e3d0a…

MALICIOUS

PDF

40.5 KB Created: 2020-08-29 16:06:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 1c003681a25167dbca9c988d53d47089 SHA-1: 32a8f6193fe9f73d25da0ad342969dd72ba6af6c SHA-256: 231e2fbab77e3d0a95d50e6bbd2ae3ae8b42878f4c683fdaff78598a383e1b68
152 Risk Score

Malware Insights

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

The PDF file was flagged by multiple critical heuristics as malicious, specifically for containing links to known malicious redirector infrastructure. The ML classifier also assigned a very high probability of maliciousness. The document body contains a URL pointing to a malicious redirector, which is likely the primary mechanism for delivering a subsequent payload or leading the user to a phishing page. The presence of numerous other URLs, while some are marked benign, suggests a link farm or obfuscation technique.

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.cc/wix?keyword=%25D1%2581%25D0%25BA%25D0%25B0%25D1%2587%25D0%25B0%25D1%2582%25D1%258C+%25D0%25BD%25D0%25B0%25D1%2588%25D0%25BF%25D0%25BE%25D1%2582%25D1%2580%25D0%25B5%25D0%25B1%25D0%25BD%25D0%25B0%25D0%25B4%25D0%25B7%25D0%25BE%25D1%2580+%25D1%2582%25D0%25BE%25D1%2580%25D1%2580%25D0%25B5%25D0%25BD%25D1%2582
    • https://cdn.shopify.com/s/files/1/0436/5575/7977/files/adsorption_process.pdf
    • https://cdn.shopify.com/s/files/1/0434/2402/2680/files/gomupebixezunizebajeworo.pdf
    • https://cdn.shopify.com/s/files/1/0429/1634/8071/files/88265950542.pdf
    • https://cdn.shopify.com/s/files/1/0435/4798/4026/files/owncloud_raspberry_pi_3.pdf
    • https://cdn.shopify.com/s/files/1/0430/1458/6521/files/2597210545.pdf
    • https://cdn.shopify.com/s/files/1/0438/2723/2918/files/flaneur_sheets_review.pdf
    • https://cdn.shopify.com/s/files/1/0432/0883/5234/files/anime_scripts_romaji.pdf
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/52733892229.pdf
    • https://cdn.shopify.com/s/files/1/0440/6899/5222/files/73798404474.pdf
    • https://cdn.shopify.com/s/files/1/0448/0018/0375/files/plural_form_of_nouns_worksheets_for_grade_5.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_off0000522d.bin
26a03fd24873b6cd435becee2695ebaa97c98d39732cceb8f3f0be9f67b25433
pdf-font-stream PDF embedded font (sfnt) at offset 0x522D 5644 bytes
font_01_sfnt_off00006492.bin
c5d671c711556946a69e8ffd28b7d5648e2a5c45eaac70c3573fe5a419ce68ff
pdf-font-stream PDF embedded font (sfnt) at offset 0x6492 14880 bytes