Malicious PDF — malware analysis report

Static analysis result for SHA-256 a525aed8a596bcbc…

MALICIOUS

PDF

33.1 KB Created: 2020-09-01 06:20:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: e9c66d697b8d582cb8aa97bbb7e793b3 SHA-1: 90899ba935a32dc2ee002c0a5725532784b3e10e SHA-256: a525aed8a596bcbcc578e5ec2499c3996417cb1468fc03ba9cfe45cc5b25d23a
154 Risk Score

Malware Insights

MITRE ATT&CK
T1566.002 Spearphishing Attachment T1059.001 PowerShell

The PDF contains embedded links, with one specifically identified as a malicious redirector. The document body, though heavily obfuscated, contains the URL 'https://ttraff.ru/wix?keyword=sika+backer+rod+data+sheet', which is flagged as malicious. The presence of a large number of external PDF links, many pointing to static.usrfiles.com, suggests a link farm or redirection strategy. 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.ru/wix?keyword=sika+backer+rod+data+sheet
    • https://static.usrfiles.com/ugd/33ab24_00f5f3dcc96f4164a9e0d942113a681c.pdf
    • https://static.usrfiles.com/ugd/e8506d_cacd50cdf1b14c91a352887863e6717c.pdf
    • https://static.usrfiles.com/ugd/9e41f0_e31e8576f6ba47e5b0a2a7500ebe5ca0.pdf
    • https://static.usrfiles.com/ugd/cd79e3_4da6a20cec11422691fa7bb127c8726b.pdf
    • https://static.usrfiles.com/ugd/a4d998_f88ee0a1e1524856aa035fb97c0d1af3.pdf
    • https://cdn.shopify.com/s/files/1/0434/4555/1271/files/estimation_and_costing_by_dutta.pdf
    • https://static.usrfiles.com/ugd/b8c837_29e5d4c05720453e9c6e518904891e01.pdf
    • https://static.usrfiles.com/ugd/b8c837_60818dd9cbe14df4bd4bec0b9b691139.pdf
    • https://static.usrfiles.com/ugd/b8c837_b591ec52d39a4c9f9a80b3a5797639c3.pdf
    • https://static.usrfiles.com/ugd/f63f29_eb34000ea90d4b7a8ff2c68a0cc9863f.pdf
    • https://static.usrfiles.com/ugd/34e21e_44f4debbb3644b3d8e39ee99f2c616c0.pdf
    • https://static.usrfiles.com/ugd/7603ae_a6771a7c668d472a851784a099a0d9d0.pdf
    • https://static.usrfiles.com/ugd/b8c837_6e0498905ca24b85803a9b1034aec93a.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_off000044e5.bin
dd056c058f46dc9fc56f9849a23c249e0f7c2d93f5a93c9da55014832cb4c904
pdf-font-stream PDF embedded font (sfnt) at offset 0x44E5 5304 bytes
font_01_sfnt_off000056e2.bin
3a56792cf179a8378d74bb8e4fc9ca7951c7c7caebfeb70753f943058851c214
pdf-font-stream PDF embedded font (sfnt) at offset 0x56E2 9612 bytes