Malicious PDF — malware analysis report

Static analysis result for SHA-256 e61a81b5004c4f96…

MALICIOUS

PDF

34.2 KB Created: 2020-08-30 08:45:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: ca14819ef24e969cd5cf7438c2de5a52 SHA-1: 42afe3b800171aea6bb88e426ca00bda0d19cc5f SHA-256: e61a81b5004c4f968c39c6cfa511be99e1b2f4d8fbd0f2227f4dc2d5d9dd32ad
152 Risk Score

Malware Insights

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

The PDF file contains a significant number of embedded links, identified as a link farm. One of these links, https://ttraff.com/wix?keyword=assassination+classroom+op, points to known malicious redirector infrastructure. The presence of a link farm and a malicious redirector suggests the document is intended to lure users to malicious sites, likely for phishing or malware delivery. The ML classifier also strongly indicated maliciousness.

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.com/wix?keyword=assassination+classroom+op
    • https://static.usrfiles.com/ugd/2486b5_68a0214fe2244a5ea7744a2d3f98f485.pdf
    • https://static.usrfiles.com/ugd/f1780b_c4684d9efa2248cda3af93fd35c3dd0f.pdf
    • https://static.usrfiles.com/ugd/b8c837_c5c1c7f912464944b0ff6b432dc6a691.pdf
    • https://static.usrfiles.com/ugd/2ac701_62c1ed2a496d46cea745cdc099f36263.pdf
    • https://static.usrfiles.com/ugd/33a16d_48cbadc0c01d4b248515929d1453fdc3.pdf
    • https://static.usrfiles.com/ugd/b8c837_1a844f21c1624ec0968bceebf0a1ccdb.pdf
    • https://static.usrfiles.com/ugd/576447_793453b03c2f4c8782da35e50adc7fc4.pdf
    • https://static.usrfiles.com/ugd/6846fe_511ab439605b4a61b68899a1f1cc7205.pdf
    • https://static.usrfiles.com/ugd/ade4e6_21121681877f4c32b79d2581505a4872.pdf
    • https://static.usrfiles.com/ugd/b8c837_c52825cdeb7a4195b3b19cbfbc2a66c6.pdf
    • https://static.usrfiles.com/ugd/7baf93_56846381fbdf48139758e2755c3a7cc0.pdf
    • https://static.usrfiles.com/ugd/b8c837_2ec6fa03b22d487ca22ac3d8f9f580e4.pdf
    • https://static.usrfiles.com/ugd/6116da_83116f097da84cef9ad0f6b378857870.pdf
    • https://static.usrfiles.com/ugd/97634b_d5c15f35425c44ecb0921b27495f7e10.pdf
    • https://static.usrfiles.com/ugd/b8c837_1f2326bf082a4b47879fbc8d03a44528.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_off00004888.bin
d72d9203304fb9f9b6223c46244ff4b1b27a421313b59bdc8d1d51daf47d7e0e
pdf-font-stream PDF embedded font (sfnt) at offset 0x4888 5068 bytes
font_01_sfnt_off000059a3.bin
c7e0af99fe1847263445ea0aff39acba9d628acc83feb315d25ba1500c7842d9
pdf-font-stream PDF embedded font (sfnt) at offset 0x59A3 10248 bytes