Malicious PDF — malware analysis report

Static analysis result for SHA-256 825feef209881ac5…

MALICIOUS

PDF

42.8 KB Created: 2020-09-05 18:02:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: ace67f71663539495e1d0eee969d3bdb SHA-1: f14bc1cee5462b1abcc5f1543f55249ae73f552d SHA-256: 825feef209881ac5dce311758f719860bbcf0a2a6beaa1302dbdb0e4ef480395
154 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file contains a large number of embedded links, many of which point to a redirector service. The primary malicious URL identified is 'https://ttraff.me/wix?keyword=writing+circle+equations+in+standard+form+worksheet', which is flagged as a malicious redirector. The document body, though heavily obfuscated, contains this URL and other benign-looking PDF links, suggesting a link farm or phishing attempt disguised as educational material. The ML classifier strongly supports the malicious verdict.

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.me/wix?keyword=writing+circle+equations+in+standard+form+worksheet
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://static.usrfiles.com/ugd/3826db_85e53083e3e74aa3bb6d892c2361ce00.pdf
    • https://static.usrfiles.com/ugd/e78b77_1b2cc7153bec411db95b51cb7e2c126e.pdf
    • https://static.usrfiles.com/ugd/5de1df_65146924c0e843d3be26e9d6a77cbe4e.pdf
    • https://static.usrfiles.com/ugd/b8c837_5ab1b82ed94e4ee587a8b5fe8d80a4df.pdf
    • https://cdn.shopify.com/s/files/1/0451/7101/5829/files/battlefield_4_free_pc_windows_10.pdf
    • https://cdn.shopify.com/s/files/1/0433/0392/7973/files/83009645351.pdf
    • https://cdn.shopify.com/s/files/1/0429/2601/4630/files/wozise.pdf
    • https://cdn.shopify.com/s/files/1/0454/5445/9030/files/design_of_isolated_footing_excel_sheet.pdf
    • https://static.usrfiles.com/ugd/724bd4_2d51665fbf964e6e92aa23d514b67e87.pdf
    • https://static.usrfiles.com/ugd/217b8a_60d197a42ead4436974ea56954e2bcf6.pdf
    • https://static.usrfiles.com/ugd/1f5cef_e8553c5e5450427aa63f783c736cf567.pdf
    • https://static.usrfiles.com/ugd/314c35_331418ef54684c6a94bcd47db625e123.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_off00005e52.bin
d51623f0f5127c556509013cdea4ff030c3341cca19c057c88726c31cb64ff38
pdf-font-stream PDF embedded font (sfnt) at offset 0x5E52 5728 bytes
font_01_sfnt_off000071bc.bin
c5c55d8fb07df7a80621a966b65224dde57b2880284598e2f73eb9f3bfeae573
pdf-font-stream PDF embedded font (sfnt) at offset 0x71BC 13896 bytes