Malicious PDF — malware analysis report

Static analysis result for SHA-256 6e8369d655f47aa9…

MALICIOUS

PDF

53.7 KB Created: 2020-07-30 02:21:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 5fdaf11a34c46b49db930eb43ab0ece3 SHA-1: 0294513ae6be178371113cd3d491c585c12292ff SHA-256: 6e8369d655f47aa9214e9002ac60422e5033e8b9feec6c845bfe8f6c4e87bce4
154 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF contains a large number of embedded links, many of which point to external websites, suggesting a link farm or redirection scheme. One URL, 'https://ttraff.ru/pify?keyword=cae+exam+samples+pdf', is flagged as a known malicious redirector. The document body, though heavily obfuscated, appears to be related to 'cae exam samples pdf', indicating 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.ru/pify?keyword=cae+exam+samples+pdf
    • http://files.seanysshop.com/uploads/1/3/0/7/130740142/ditida.pdf
    • http://files.philomathopenstudios.com/uploads/1/3/0/9/130968942/7650205.pdf
    • http://files.jagregina.com/uploads/1/3/1/8/131871535/lurusut.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://cdn.shopify.com/s/files/1/0428/0962/2695/files/rukagepidamiwitiwifo.pdf
    • https://cdn.shopify.com/s/files/1/0428/7863/2095/files/zuxopetekopejijifet.pdf
    • https://cdn.shopify.com/s/files/1/0434/4607/5542/files/vikanupabapavavetax.pdf
    • https://cdn.shopify.com/s/files/1/0430/2517/0595/files/74627543088.pdf
    • https://cdn.shopify.com/s/files/1/0428/3318/2886/files/32194255844.pdf
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/lovukapovilelogitolosir.pdf
    • https://cdn.shopify.com/s/files/1/0428/1643/8438/files/medikugikuvesekojo.pdf
    • https://cdn.shopify.com/s/files/1/0432/8197/3403/files/1716925506.pdf
    • https://cdn.shopify.com/s/files/1/0430/4352/0665/files/vifetubukamufaxasunox.pdf
    • https://cdn.shopify.com/s/files/1/0435/9382/6463/files/fivukurilino.pdf
    • https://cdn.shopify.com/s/files/1/0431/1485/6610/files/68007744267.pdf
    • https://cdn.shopify.com/s/files/1/0434/5144/9496/files/vituma.pdf
    • https://cdn.shopify.com/s/files/1/0437/1261/0472/files/86058705320.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_off00008c1d.bin
b608a80607d6a29a48a1dd0e4a9da7a66d12bd4253a24500afe72270fa8d6c27
pdf-font-stream PDF embedded font (sfnt) at offset 0x8C1D 4628 bytes
font_01_sfnt_off00009be8.bin
570967ca9396cf015c8bcdeda114bda3ff68b005a8952168d3964d04d190b180
pdf-font-stream PDF embedded font (sfnt) at offset 0x9BE8 14296 bytes