Malicious PDF — malware analysis report

Static analysis result for SHA-256 81c3f21ef5858366…

MALICIOUS

PDF

50.8 KB Created: 2020-08-08 15:46:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 7f5efac0f8b64d5d8c3ed75336dc8e4b SHA-1: 750de77f1acc250a838d643a50613b93912fb9e0 SHA-256: 81c3f21ef5858366144d3c530d2d143d37c0b70b1f451d081aee95cef4c4a3c5
154 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded links, with the primary one pointing to a known malicious redirector. The ML classifier strongly indicated maliciousness, and the presence of a link farm suggests an attempt to manipulate search engine results or distribute malicious content. No scripts were extracted, but the embedded URLs are the primary indicators of malicious intent.

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/wb?keyword=angina%20inestable%20diagnostico%20pdf
    • http://files.kentcrusaders.com/uploads/1/3/0/7/130740193/f916547723c.pdf
    • http://files.instakats.com/uploads/1/3/0/8/130814680/nufaporigedete_jotim_xuvegerof.pdf
    • http://files.imagescenter.com/uploads/1/3/0/9/130969545/vemawewasipe.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • http://www.daltonmaag.com/
    • https://cdn.shopify.com/s/files/1/0434/3998/0711/files/lizevabi.pdf
    • https://cdn.shopify.com/s/files/1/0430/3031/5159/files/4th_grade_spelling_list.pdf
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/22650439267.pdf
    • https://cdn.shopify.com/s/files/1/0431/9353/2573/files/64342574508.pdf
    • https://cdn.shopify.com/s/files/1/0427/7462/6470/files/lonubawejaf.pdf
    • https://cdn.shopify.com/s/files/1/0432/2341/6995/files/wogix.pdf
    • https://cdn.shopify.com/s/files/1/0437/8486/3893/files/mechanics_of_materials_3rd_edition_philpot.pdf
    • https://cdn.shopify.com/s/files/1/0433/9813/5966/files/77735118949.pdf
    • https://cdn.shopify.com/s/files/1/0431/8943/6580/files/sikukawagofemabekiwukezi.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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00006ce4.bin
6be3347e11f01d554958e873bbc7e3d85a8662a3f462d3fa44239b2cb3084f25
pdf-font-stream PDF embedded font (sfnt) at offset 0x6CE4 5144 bytes
font_01_sfnt_off00007e66.bin
1cccf70f59f1b956dc2d0517e7015dc0c45afd096d4628210ea55395dd1405ac
pdf-font-stream PDF embedded font (sfnt) at offset 0x7E66 16156 bytes
font_02_sfnt_off0000aeaf.bin
b50a2106bf82917db0cd3cf88f63c5e8cc3298b343ace5cffc591b35df33d24c
pdf-font-stream PDF embedded font (sfnt) at offset 0xAEAF 4324 bytes