Malicious PDF — malware analysis report

Static analysis result for SHA-256 f27c6eff0fa20c4b…

MALICIOUS

PDF

50.6 KB Created: 2020-07-29 14:57:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: f2d166dfb813226f5bc6c8c6c8125f76 SHA-1: 20280b24efeacf2af8da633d47913a9efb4c1845 SHA-256: f27c6eff0fa20c4b70152aa478091544470487c54b1dabfc5f6fb836dcfc10a4
152 Risk Score

Malware Insights

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

The PDF contains a significant number of embedded links, identified as a link farm, with a critical heuristic firing for malicious redirector links. The primary malicious URL points to a redirector service, suggesting an attempt to lure users to potentially harmful content. The document body is heavily obfuscated and contains metadata indicating it was generated by wkhtmltopdf, a tool often used to create documents for SEO manipulation or to disguise malicious content.

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/wb?keyword=fibrilacion%20auricular%20electrocardiograma%20pdf
    • http://files.sequatchiecountyband.org/uploads/1/3/0/9/130969551/1708227.pdf
    • http://files.100percentcajun.com/uploads/1/3/1/0/131070751/6209751.pdf
    • http://files.ftpiercemasons.org/uploads/1/3/1/6/131606953/9351125.pdf
    • http://files.sciencelife.org/uploads/1/3/1/6/131637953/gotimaripaw-fekapa.pdf
    • http://files.cochocolatefests.com/uploads/1/3/0/9/130969772/gobizeninewoto-pitizekaze-zopolepafukamas.pdf
    • http://files.sciencelife.org/uploads/1/3/
    • https://cdn.shopify.com/s/files/1/0432/5569/3470/files/rururu.pdf
    • https://cdn.shopify.com/s/files/1/0437/2670/0696/files/nizarepororizidofokegemup.pdf
    • https://cdn.shopify.com/s/files/1/0429/9712/1178/files/vilodoponenijajozubexiz.pdf
    • https://cdn.shopify.com/s/files/1/0427/4061/3286/files/92389968470.pdf
    • https://cdn.shopify.com/s/files/1/0430/3699/9842/files/kutexubajakebizikenabuz.pdf
    • https://cdn.shopify.com/s/files/1/0429/6101/0842/files/wepobipufaw.pdf
    • https://cdn.shopify.com/s/files/1/0429/9191/1066/files/51589573874.pdf
    • https://cdn.shopify.com/s/files/1/0432/0745/8975/files/43801425013.pdf
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/gaxedisurerikemamezawapux.pdf
    • https://cdn.shopify.com/s/files/1/0431/6128/8868/files/webigexeminifijev.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_off000084ab.bin
2c89a767d358e30ce27e250bacc7516267d7ab4d1de07fd839fabe385882ba10
pdf-font-stream PDF embedded font (sfnt) at offset 0x84AB 5272 bytes
font_01_sfnt_off00009673.bin
09ca432cf3e87cb8e1dce47fde6fae64a61d3869dc10ff7640d4b3a6afaeb376
pdf-font-stream PDF embedded font (sfnt) at offset 0x9673 11316 bytes