Malicious PDF — malware analysis report

Static analysis result for SHA-256 de8682b973f4263b…

MALICIOUS

PDF

36.2 KB Created: 2020-09-17 12:20:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 3e418673608a6e00b86cbeb5a8383daa SHA-1: 44e040e97d93adc6f8d5ae1059d184dc366b86fe SHA-256: de8682b973f4263b553b44ca7e03dd18a677975f8b1d27504babc51c85fa41c6
128 Risk Score

Malware Insights

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

The PDF contains a mass external link farm, with many links pointing to PDF files hosted on various domains. One prominent link, 'https://ttraff.me/wix?keyword=adding+s+or+es+to+verbs+worksheet+pdf', is flagged as a malicious redirector. The document body, though heavily obfuscated, contains references to a worksheet and includes this malicious URL, suggesting a lure to download further malicious content. The presence of a 'Visual download / call-to-action button lure' heuristic further supports this. The file is generated by wkhtmltopdf, a tool often used to create PDFs from web content, which may have been used here to disguise the malicious links.

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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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.me/wix?keyword=adding+s+or+es+to+verbs+worksheet+pdf
    • http://bitisuro.ksuflashathon.com/uploads/1/3/1/1/131164312/vedokuxameb.pdf
    • http://files.houstons.net/uploads/1/3/1/4/131453919/novimetosanegak.pdf
    • http://files.cribworksdigitalaudio.com/uploads/1/3/1/3/131379174/aadd28902c346.pdf
    • https://da1b6f5d-d71a-4b99-b3b1-f3372cbab093.filesusr.com/ugd/1b6cec_7afe63b41ab943609a7824a3e7e72cea.pdf?index=true
    • https://162b3c93-4260-4db2-978d-597113c829d0.filesusr.com/ugd/76aeb6_7347728ba73c46ce946108bacbcb3b2b.pdf?index=true
    • https://970a87bf-addb-4bb1-9fc6-97941262d760.filesusr.com/ugd/f3bfbb_f49bcfc37fa5430eb1703639e55dfee8.pdf?index=true
    • https://5742576d-b164-42c1-a8e8-9fc50bc3eac1.filesusr.com/ugd/0cd3a8_7c59e93c2aa248da946183b4eba3c1c2.pdf?index=true
    • https://0163a90f-ca36-4cb9-af0a-4d5cd7de5019.filesusr.com/ugd/b14caa_056dd54f297342abae8f469cca28175d.pdf?index=true
    • https://c65613ff-4031-4f80-9dd9-3f1892ad88b1.filesusr.com/ugd/c638b7_250c0e03ac5244f38ad4b1f84cd6f6b8.pdf?index=true
    • https://aa36b373-23db-41b3-beb0-6156902c5535.filesusr.com/ugd/a382ee_5941bc222e3b4327bec52f258286cd7b.pdf?index=true
    • https://b3d27323-e901-4a71-a331-b5b866a20535.filesusr.com/ugd/dc6899_46ed57c084ef438a87b9197323410a0b.pdf?index=true
    • https://0b76928b-ffbc-4246-b4d5-1159e7e6094f.filesusr.com/ugd/3f0e57_65624776a67c4b8199c28d347f281ec4.pdf?index=true
    • https://81394e64-2694-4571-b540-23f0e00ef9bb.filesusr.com/ugd/1e533a_1c33539100ed4a81958607ffe62c9e0e.pdf?index=true
    • 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_off00004dc2.bin
d1d3419c27673e882eee1510c589048967e7b9df2637e784d4ae9064ecb439f9
pdf-font-stream PDF embedded font (sfnt) at offset 0x4DC2 5404 bytes
font_01_sfnt_off0000603b.bin
01c401178f809dd1edfeb485bd90c29af984d1ea63fa431699107ed7adb87f9d
pdf-font-stream PDF embedded font (sfnt) at offset 0x603B 10500 bytes