Malicious PDF — malware analysis report

Static analysis result for SHA-256 7fd0a4a540761f58…

MALICIOUS

PDF

66.2 KB Created: 2020-09-12 15:04:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 2c53f62c16abdea834702c467eaf7169 SHA-1: 794e9f2667b7ceeea10a38de8851542024d4f1b6 SHA-256: 7fd0a4a540761f587968c210f907b639ba08446d4726d70c9559a88c5b40b3b3
154 Risk Score

Malware Insights

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

The PDF contains embedded links, one of which is a redirector pointing to a URL containing 'android 9 api changes', suggesting a lure for users interested in technical information. The PDF also hosts a large number of other PDF links, indicating a potential link farm or SEO manipulation tactic. The ML classifier strongly flagged this PDF as malicious, and the presence of redirector links further supports 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.link/wix?keyword=android+9+api+changes
    • http://files.obmghk.com/uploads/1/3/1/4/131437711/8056672.pdf
    • http://katavu.thehopkinsgallerystore.com/uploads/1/3/1/8/131872055/344833.pdf
    • http://files.sathiavanee-veeramoothoo.com/uploads/1/3/1/8/131871891/jidutemepupaz.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://cdn.shopify.com/s/files/1/0439/1193/8216/files/22920809498.pdf
    • https://cdn.shopify.com/s/files/1/0437/4475/5866/files/15284780627.pdf
    • https://cdn.shopify.com/s/files/1/0462/7929/5136/files/sutarebew.pdf
    • https://cdn.shopify.com/s/files/1/0429/6402/5493/files/linkedin_logo_usage_guidelines.pdf
    • https://cdn.shopify.com/s/files/1/0433/6762/8950/files/pukokix.pdf
    • https://cdn.shopify.com/s/files/1/0481/3691/3049/files/emergency_action_plan_checklist.pdf
    • https://cdn.shopify.com/s/files/1/0434/5040/0928/files/gujezof.pdf
    • https://static.usrfiles.com/ugd/a7074a_ccf1c023645d458996ca1d1d809a5bcc.pdf
    • https://static.usrfiles.com/ugd/cf5aa9_59fefbe8e76040ae95811edfaad187f7.pdf
    • https://static.usrfiles.com/ugd/1cc777_24437f49eb5242e88d590c14ad385968.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_off0000b631.bin
164ffcc4a3ae23839566ef4161686fcf9a12ed95c874d9161b0c86e982dedf18
pdf-font-stream PDF embedded font (sfnt) at offset 0xB631 5448 bytes
font_01_sfnt_off0000c8b5.bin
f8752ee86815ab31dc45a62b8ed7c5806cd383eba0ea088fc5be6373f2959767
pdf-font-stream PDF embedded font (sfnt) at offset 0xC8B5 16488 bytes