Malicious PDF — malware analysis report

Static analysis result for SHA-256 9b420897c8fe0387…

MALICIOUS

PDF

53.0 KB Created: 2020-08-02 17:37:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: c640066d3a7b44ea86dfd3ff421d66e4 SHA-1: f857d35d5e5e7f52779481124c3d35a10eab7ef4 SHA-256: 9b420897c8fe0387af9af32c8e50fb198e1084a3eb0107f224f48f9e823235bd
152 Risk Score

Malware Insights

MITRE ATT&CK
T1566.002 Spearphishing Attachment T1059.001 PowerShell

The PDF contains multiple embedded links, with one identified as a malicious redirector. The ML classifier strongly flagged this PDF as malicious. The primary attack vector appears to be a link farm designed to redirect users to malicious sites, as indicated by the 'PDF_SEO_LINK_FARM' and 'PDF_MALICIOUS_REDIRECTOR_LINK' heuristics. The document body contains obfuscated text and a URL that likely serves as the initial lure.

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.cc/pify?keyword=mi+state+abbreviation
    • http://files.wechoosetoday.com/uploads/1/3/1/1/131163898/be2b14.pdf
    • http://files.tsidieselworxparts.com/uploads/1/3/2/6/132681992/f252486a92fa9ad.pdf
    • http://files.dukesbicycles.com/uploads/1/3/1/1/131163684/3600618.pdf
    • https://cdn.shopify.com/s/files/1/0432/9265/5780/files/bamiweduj.pdf
    • https://cdn.shopify.com/s/files/1/0429/0579/6774/files/56093713292.pdf
    • https://cdn.shopify.com/s/files/1/0432/5244/9444/files/zadupixoliko.pdf
    • https://cdn.shopify.com/s/files/1/0437/3174/6967/files/34470259279.pdf
    • https://cdn.shopify.com/s/files/1/0429/1392/3228/files/xovojetenipuzez.pdf
    • https://cdn.shopify.com/s/files/1/0429/3564/8409/files/gobomifopate.pdf
    • https://cdn.shopify.com/s/files/1/0430/3601/6803/files/xesiteraka.pdf
    • https://cdn.shopify.com/s/files/1/0431/5090/1402/files/monapetovagupitejabe.pdf
    • https://cdn.shopify.com/s/files/1/0434/0203/5351/files/65551613369.pdf
    • https://cdn.shopify.com/s/files/1/0437/6877/4814/files/26326995945.pdf
    • https://cdn.shopify.com/s/files/1/0427/4749/4567/files/levidalujidetiwutoz.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_off0000889c.bin
befefacf67c9dce525caedb13fe8f3dd27e4de6b4dd986f9ae51ea3a113eece6
pdf-font-stream PDF embedded font (sfnt) at offset 0x889C 4852 bytes
font_01_sfnt_off00009939.bin
a37491d12a1f47746333324736db1273071d2895d1ef51250066aabdf2423e40
pdf-font-stream PDF embedded font (sfnt) at offset 0x9939 15000 bytes