Malicious PDF — malware analysis report

Static analysis result for SHA-256 aa7dbc4e803ab624…

MALICIOUS

PDF

71.0 KB Created: 2021-04-21 08:12:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-06-17
MD5: e55fde4fd427c9d37e3ff5f51b9e6f28 SHA-1: 2d68a69eef61b192cd7abcc092d013f94482b77c SHA-256: aa7dbc4e803ab6244cb4d7b1b62f6c8e15e9fc6aaaa94cf896b98eb78748d739
124 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF contains numerous embedded links, many pointing to disposable domains, and is flagged by ML classifiers and ClamAV as malicious. The document body, though heavily obfuscated, appears to be a lure for external websites. The presence of embedded links suggests an attempt to redirect users to malicious sites, likely for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.8132

Heuristics 4

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • External URI info PDF_URI
    PDF contains an external URL action
  • 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 http://seiary.com/sites/default/files/webform/rec/kutovaduro.pdf In PDF document text
    • https://ambrose.edu/sites/default/files/webform/padubomi.pdfIn PDF document text
    • https://www.blplegal.com/sites/default/files/webform/32112495638.pdfIn PDF document text
    • https://www.pharoxglobal.com/sites/default/files/webform/27804174203.pdfIn PDF document text
    • https://www.a1touchsolution.nl/sites/default/files/73086307569.pdfIn PDF document text
    • https://www.woonsocketri.org/system/temporary/webform/konoju.pdfIn PDF document text
    • https://www.enwidth.com/sites/default/files/webform/resumes/48862039041.pdfIn PDF document text
    • https://ambrose.edu/sites/default/files/webform/fenalop.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/YTWXjIUwRh0/uplcv?utm_term=what+kind+of+bird+has+a+yellow+beakPDF link annotation
    • https://printandmail.princeton.edu/system/files/webform/50156150340.pdfIn PDF document text
    • https://www.ice.cam.ac.uk/sites/www.ice.cam.ac.uk/files/webform/tivajojisepizoni.pdfIn PDF document text
    • https://www.vub.be/sites/vub/files/webform/lijulur.pdfIn PDF document text
    • https://www.vub.be/sites/vub/files/webform/pagilavamuvawasaxega.pdfIn PDF document text
    • https://www.ice.cam.ac.uk/sites/www.ice.cam.ac.uk/files/webform/50075528518.pdfIn PDF document text
    • https://gradfutures.princeton.edu/system/files/webform/ninavixokamorul.pdfIn PDF document text
    • https://lib.asu.edu/system/files/webform/61431168480.pdfIn PDF document text
    • http://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e91e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE91E 5404 bytes
SHA-256: 833e82d172311faa8818b459fd2ad14af208f5e65f8119bc2825c2785f3009f0
font_01_sfnt_off0000fb96.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFB96 10004 bytes
SHA-256: cc2c2993e53252ae9881433acafa7ee894f4ee89359fa2d8b3f1c61740e6d6ad