Malicious PDF — malware analysis report

Static analysis result for SHA-256 b73a9d20650cbad7…

MALICIOUS

PDF

46.5 KB Created: 2020-08-22 04:05:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 0a371bf766e5e274453c99f11f9f2776 SHA-1: 8fe481c34015213473846882169e45715639948a SHA-256: b73a9d20650cbad7222e1a091b83fbdc7081c9da480116549e68b6725798ee44
152 Risk Score

Malware Insights

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

The PDF contains a mass of external links, many pointing to benign content, but one critical link redirects to a known malicious infrastructure. The document body, though heavily obfuscated, contains the URL 'https://ttraff.ru/pify?keyword=browser+extension+apps+for+android', which is flagged as a malicious redirector. This suggests the document's primary purpose is to trick users into visiting this malicious URL, likely for further exploitation or phishing.

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=browser+extension+apps+for+android
    • http://laton.theoldrectorynursinghome.org/uploads/1/3/0/7/130775982/5450028.pdf
    • https://cdn.shopify.com/s/files/1/0429/1290/7427/files/sebawodufesatomigunakefel.pdf
    • https://cdn.shopify.com/s/files/1/0436/5107/2153/files/project_management_a_managerial_approach.pdf
    • https://cdn.shopify.com/s/files/1/0433/0065/1158/files/formato_de_certificado_medico_de_farmacias_similares.pdf
    • https://cdn.shopify.com/s/files/1/0432/7571/4715/files/30779824145.pdf
    • https://cdn.shopify.com/s/files/1/0433/4551/0568/files/43331691568.pdf
    • https://cdn.shopify.com/s/files/1/0451/6813/2250/files/risk_management_plan_construction.pdf
    • https://cdn.shopify.com/s/files/1/0437/8833/7313/files/91523633118.pdf
    • https://cdn.shopify.com/s/files/1/0440/3052/5590/files/mibevomafatojaruvedi.pdf
    • https://cdn.shopify.com/s/files/1/0431/2144/2977/files/3973309360.pdf
    • https://cdn.shopify.com/s/files/1/0434/2002/4989/files/dagexar.pdf
    • https://cdn.shopify.com/s/files/1/0430/4646/9793/files/zikugivatepixegoxofe.pdf
    • https://cdn.shopify.com/s/files/1/0434/6881/6544/files/kelof.pdf
    • https://cdn.shopify.com/s/files/1/0431/3789/2509/files/82975969721.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_off0000766f.bin
bc2d88d1d54a075a9dc78ad5493ca877ce7f63f16e47e00d3431b70bc26a6297
pdf-font-stream PDF embedded font (sfnt) at offset 0x766F 5212 bytes
font_01_sfnt_off00008854.bin
9620e26d30ef2d2fd4563cb2dd39bc467be352cb6399d147f9ffe7c673c2d537
pdf-font-stream PDF embedded font (sfnt) at offset 0x8854 10688 bytes