Malicious PDF — malware analysis report

Static analysis result for SHA-256 df168896451c6c86…

MALICIOUS

PDF

41.9 KB Created: 2020-08-30 13:16:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 2dd8fb4d718964e34eec90f60efb80d2 SHA-1: cfa537d9709fce3e248d4aba4cabc42f791380ad SHA-256: df168896451c6c86fecfba465f70d6dcb3da743e655db6103ce0fb7073c2b299
152 Risk Score

Malware Insights

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

The PDF contains numerous embedded links, including one pointing to a known malicious redirector at 'ttraff.ru'. The document body, though heavily obfuscated, appears to contain keywords related to educational worksheets, likely a lure. The ML classifier strongly indicated maliciousness, and the presence of a redirector link confirms the intent to lead the user to a harmful 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/wix?keyword=defining+relative+clauses+esl+worksheets
    • https://cdn.shopify.com/s/files/1/0427/4988/6620/files/96985458628.pdf
    • https://cdn.shopify.com/s/files/1/0435/1223/4139/files/14078381600.pdf
    • https://cdn.shopify.com/s/files/1/0435/7462/4419/files/angular_5_data_binding_form.pdf
    • https://cdn.shopify.com/s/files/1/0459/6763/8695/files/43159988610.pdf
    • https://cdn.shopify.com/s/files/1/0440/6237/6101/files/fipivizagaxokaritubu.pdf
    • https://static.usrfiles.com/ugd/b98abb_dc06d81da3674811b3cdc03da0b9e7c6.pdf
    • https://static.usrfiles.com/ugd/c63dba_05103d7cc1af4027b65203863434266d.pdf
    • https://static.usrfiles.com/ugd/b8c837_664249c81da44ab2969ba9e06293e833.pdf
    • https://static.usrfiles.com/ugd/b8c837_6cbaf4432a3240aebeb8cc751c0e4c84.pdf
    • https://static.usrfiles.com/ugd/daca0d_4066c32fdaea447398408ffafecee76b.pdf
    • https://cdn.shopify.com/s/files/1/0433/5131/0488/files/65364677794.pdf
    • https://cdn.shopify.com/s/files/1/0437/2407/9254/files/multi_platform_games_android_pc.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_off00006674.bin
1fee9bea9a123810b5834e0047d233e6328d514172a3dd5b2e18323918da954d
pdf-font-stream PDF embedded font (sfnt) at offset 0x6674 5356 bytes
font_01_sfnt_off000078c7.bin
418ef30939889dfeb8edb03c223ce61e96f0b9ee2e303fa97d662c9f4f385623
pdf-font-stream PDF embedded font (sfnt) at offset 0x78C7 9936 bytes