Malicious PDF — malware analysis report

Static analysis result for SHA-256 fd739d0ffdd51303…

MALICIOUS

PDF

39.3 KB Created: 2020-08-31 09:25:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 1f6be97a9a474f9ff24a502ec62e79ad SHA-1: e189fd5e3c0b41e99d2060ecf4aa2b6436a3826e SHA-256: fd739d0ffdd513036f9a5a97cfef23a1844157a77db19d7daf350839c5f6081d
152 Risk Score

Malware Insights

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

The PDF file contains numerous embedded links, with one specifically pointing to a known malicious redirector. The document body, though heavily obfuscated, contains the URL 'https://ttraff.cc/wix?keyword=the+economic+implications+of+learning+by+doing+pdf', suggesting a lure to a malicious site. The presence of a large number of external PDF links, many hosted on 'static.usrfiles.com', indicates a link farm designed to distribute malicious content. No scripts were extracted from this sample.

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.cc/wix?keyword=the+economic+implications+of+learning+by+doing+pdf
    • https://static.usrfiles.com/ugd/158fb9_6e3547f6af684cc685aba1ce54905930.pdf
    • https://static.usrfiles.com/ugd/429b25_f0703aba73c743ae91fcee3d8c039382.pdf
    • https://static.usrfiles.com/ugd/b8c837_928d4ae96bb3437abc9af4af673dde39.pdf
    • https://static.usrfiles.com/ugd/ea9bdf_1d932d9ec8b84213b8b5dbc7783d35bd.pdf
    • https://static.usrfiles.com/ugd/b8c837_903caf40da2c4745b178f218f357d188.pdf
    • https://static.usrfiles.com/ugd/98e298_67e52138da664486a28343231b6a834c.pdf
    • https://static.usrfiles.com/ugd/de3d83_7d9bf47cc081424483a8fd8a7fd01234.pdf
    • https://static.usrfiles.com/ugd/c1de29_2831e20a39e04c6ba277ccca1de9f5f9.pdf
    • https://static.usrfiles.com/ugd/d1c05f_3919f5e799ea496991cf8f32836840c6.pdf
    • https://static.usrfiles.com/ugd/1decf9_07615f6aa1744b22b111b4a688897817.pdf
    • https://static.usrfiles.com/ugd/bd5c68_dbf485bd097b4adb89a9a1314c666ea7.pdf
    • https://static.usrfiles.com/ugd/b8c837_e9f61959076245ed9fa00c96a6d56967.pdf
    • https://static.usrfiles.com/ugd/b8c837_8f731a8c4a674aac823e2ccfa3b2ae6a.pdf
    • https://cdn.shopify.com/s/files/1/0431/3861/3399/files/academic_ielts_writing_task_1_sample_answers.pdf
    • https://cdn.shopify.com/s/files/1/0440/8036/5720/files/applicant_tracking_system_open_source.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_off000057b3.bin
32d29903efe51a979a6f9d7b17723b3f83dc42507f1ee427454e840f0aad902b
pdf-font-stream PDF embedded font (sfnt) at offset 0x57B3 5760 bytes
font_01_sfnt_off00006b0f.bin
5e92cb11f5c27e4b58c5163eacc8b101e7f93733044543ccb2ebe588b9bb9470
pdf-font-stream PDF embedded font (sfnt) at offset 0x6B0F 11252 bytes