Malicious PDF — malware analysis report

Static analysis result for SHA-256 db53f8e0b8001bef…

MALICIOUS

PDF

41.2 KB Created: 2020-08-22 14:10:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 1035122354678a6c34488758c468a185 SHA-1: 5a58ea347919b0698cca1c114ce9f81c90469854 SHA-256: db53f8e0b8001bef0f46ef61546672a3bbbcdb30e61765e5cba1d0ceb9b56692
152 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1566.002 Spearphishing Link

The PDF file contains numerous embedded URLs, with a critical heuristic firing indicating a malicious redirector link to 'https://ttraff.ru/pify?keyword=best+android+tv+apps+apk'. Another critical heuristic identified this as a PDF link farm, with 24 external links, many hosted on cdn.shopify.com. The ML classifier strongly flagged this PDF as malicious. The document body, though heavily corrupted, contains fragments of URLs and metadata suggesting it was generated by wkhtmltopdf, a tool sometimes used to create malicious PDFs for SEO poisoning or phishing campaigns.

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=best+android+tv+apps+apk
    • http://files.emkdgenealogy.com/uploads/1/3/1/4/131453250/4991405.pdf
    • http://jasuw.genevievemariedavis.com/uploads/1/3/1/4/131452883/mufijuruna.pdf
    • https://cdn.shopify.com/s/files/1/0432/8049/8841/files/96391847070.pdf
    • https://cdn.shopify.com/s/files/1/0434/0655/7341/files/anticoagulantes_orales_y_parenterales.pdf
    • https://cdn.shopify.com/s/files/1/0448/3507/8306/files/airport_codes_iata.pdf
    • https://cdn.shopify.com/s/files/1/0434/1363/5226/files/17378144880.pdf
    • https://cdn.shopify.com/s/files/1/0431/2370/3969/files/pugexupunotudetafo.pdf
    • https://cdn.shopify.com/s/files/1/0431/9058/3458/files/cluster_computing_abstract.pdf
    • https://cdn.shopify.com/s/files/1/0431/5840/5274/files/ramuxedowo.pdf
    • https://cdn.shopify.com/s/files/1/0440/9291/5864/files/malignant_pleural_effusion_management_guidelines.pdf
    • https://cdn.shopify.com/s/files/1/0430/5358/0439/files/51758147310.pdf
    • https://cdn.shopify.com/s/files/1/0432/3134/6856/files/39143346261.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_off00006394.bin
461e0be22a7a4b7b6f057b930c83cbfb5b7a49a8accb3fe6593b3126d0d06369
pdf-font-stream PDF embedded font (sfnt) at offset 0x6394 5092 bytes
font_01_sfnt_off000074fd.bin
add6ea168b27285c5a30141e119f24feb11b6755480dc247acd1854a24377640
pdf-font-stream PDF embedded font (sfnt) at offset 0x74FD 10364 bytes