Malicious PDF — malware analysis report

Static analysis result for SHA-256 e5dc5de3584b0a7f…

MALICIOUS

PDF

40.1 KB Created: 2020-08-06 11:05:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 0a5d5cf380b17df24978a92d56445c83 SHA-1: 24c44dd229cbb03dc58dc4ae7d9044d6bd27242c SHA-256: e5dc5de3584b0a7f47140bb35918054062eaf305ce7048afa81335b11b984e35
152 Risk Score

Malware Insights

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

The PDF was flagged as malicious by a machine learning classifier and contains a critical heuristic indicating it links to known malicious redirector infrastructure. The document body itself is heavily obfuscated but contains a URL that appears to be the primary lure. The presence of a large number of external PDF links, many hosted on Shopify, suggests a link farm or SEO manipulation tactic, potentially to distribute further malicious content or to obscure the true malicious destination.

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=abc+costing+system+pdf
    • http://files.cellofest.co.uk/uploads/1/3/1/3/131379578/totabemetumodew.pdf
    • http://files.flyroddersheaven.net/uploads/1/3/0/9/130969206/360716accf.pdf
    • http://sitoro.atomysupport.com/uploads/1/3/2/3/132303189/3323154.pdf
    • https://cdn.shopify.com/s/files/1/0433/4390/4927/files/68521377863.pdf
    • https://cdn.shopify.com/s/files/1/0430/8893/7120/files/mewusebetijurupidow.pdf
    • https://cdn.shopify.com/s/files/1/0432/5877/3662/files/87828516527.pdf
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/93527538138.pdf
    • https://cdn.shopify.com/s/files/1/0430/3765/5191/files/49535114485.pdf
    • https://cdn.shopify.com/s/files/1/0440/6149/1352/files/91851715834.pdf
    • https://cdn.shopify.com/s/files/1/0428/9436/0743/files/40236387638.pdf
    • https://cdn.shopify.com/s/files/1/0428/8544/7833/files/bangladesh_bank_job_preparation_book.pdf
    • https://cdn.shopify.com/s/files/1/0429/2732/5343/files/vefukulopisuwadojijo.pdf
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/10542261424.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_off00005f35.bin
f537957b1090d68b217ba1a0dbba39338ccb0209d578c2ec913a2a2b46e3ddc8
pdf-font-stream PDF embedded font (sfnt) at offset 0x5F35 5368 bytes
font_01_sfnt_off00007179.bin
f3b2bee412bf791c6c789abaebd54537f543d7663e7768ae0b30e78957009bf5
pdf-font-stream PDF embedded font (sfnt) at offset 0x7179 10080 bytes