Malicious PDF — malware analysis report

Static analysis result for SHA-256 63cf8190eecd745f…

MALICIOUS

PDF

43.6 KB Created: 2020-08-06 21:52:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 6012bbbccbd5f8000c983ec293b99922 SHA-1: 34fc36861b43cc61a41747cc64e5c953392702a0 SHA-256: 63cf8190eecd745f86a1695927e6fb96122254f7a121e615dcd746d48fba7735
154 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a large number of external links, many of which point to benign Shopify URLs, but one critical link directs to a known malicious redirector. The document body, though heavily obfuscated, contains text related to job interviews and the malicious URL, suggesting a lure. 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.com/pify?keyword=common+questions+and+answers+in+job+interview+pdf
    • http://files.katiecakesbakery.com/uploads/1/3/1/6/131606583/suvebomukemuja.pdf
    • http://files.schomesnc.com/uploads/1/3/1/3/131383383/1550015.pdf
    • http://files.klynnewagner.com/uploads/1/3/0/7/130776602/gigixonevis-gosumazujupofus-junepajomuj-jofidafufemumof.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://cdn.shopify.com/s/files/1/0431/6318/9405/files/ap_stylebook_2015.pdf
    • https://cdn.shopify.com/s/files/1/0430/0704/9887/files/65097619870.pdf
    • https://cdn.shopify.com/s/files/1/0428/3272/4124/files/39923068749.pdf
    • https://cdn.shopify.com/s/files/1/0429/9508/9571/files/icici_bank_details.pdf
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/kurejala.pdf
    • https://cdn.shopify.com/s/files/1/0434/6000/1954/files/mowud.pdf
    • https://cdn.shopify.com/s/files/1/0434/5593/8720/files/sivaxumiba.pdf
    • https://cdn.shopify.com/s/files/1/0427/4287/4278/files/lupavaxowasigeb.pdf
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/surorut.pdf
    • https://cdn.shopify.com/s/files/1/0436/2466/1154/files/27004109654.pdf
    • https://cdn.shopify.com/s/files/1/0430/9313/1425/files/77644044513.pdf
    • https://cdn.shopify.com/s/files/1/0434/5462/7993/files/binomial_theorem_iit_notes.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_off00006b8c.bin
b240b618f94c76910c81dded330003279aa4a38defb233a63924b050281a1d30
pdf-font-stream PDF embedded font (sfnt) at offset 0x6B8C 5552 bytes
font_01_sfnt_off00007e63.bin
de8bf53a2801452d8bd5b932fd5cfc201be4ec23f6bd7d4b83fd2ebf154b521d
pdf-font-stream PDF embedded font (sfnt) at offset 0x7E63 10072 bytes