Malicious PDF — malware analysis report

Static analysis result for SHA-256 6a55ddff9bbbfb3d…

MALICIOUS

PDF

96.0 KB Created: 2021-04-11 15:02:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-11
MD5: b0374be3bb6e12c80d3f2219772bb404 SHA-1: 74f3ee0091c9f00b228e639e32d5664629c182c8 SHA-256: 6a55ddff9bbbfb3d3afbd67b60cdffc8a5b21e4b78b72976140705f7ba3e2d23
124 Risk Score

Malware Insights

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

The PDF file was flagged by multiple heuristics, including a machine learning classifier and ClamAV, indicating malicious intent. The presence of numerous external URIs, some pointing to potentially disposable hosting, suggests a link farm designed to redirect users. Although no scripts were explicitly extracted, the PDF structure and heuristic firings point towards a phishing or malware distribution attempt, likely using embedded links to host malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9452

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 https://www.mothercare.ro/sites/default/files/webform/resumes/susumijifiwef.pdf In PDF document text
    • https://extranet.blanchisserie-toulousaine-de-sante.com/sites/extranet.blanchisserie-toulousaine-de-sante.com/files/documents/justificatifs/ziseriwutekezarog.pdfIn PDF document text
    • https://www.enwidth.com/sites/default/files/webform/resumes/22435641867.pdfIn PDF document text
    • https://www.pharoxglobal.com/sites/default/files/webform/7322176875.pdfIn PDF document text
    • https://www.enwidth.com/sites/default/files/webform/resumes/48862039041.pdfIn PDF document text
    • https://vectorcorp.net/sites/default/files/webform/resume/sowasipaxezok.pdfIn PDF document text
    • https://www.uts.cw/sites/default/files/webform/96040264728.pdfIn PDF document text
    • https://grossenbacher.co.nz/en/system/files/avoidance-training-certificates/13471650610.pdfIn PDF document text
    • https://extranet.blanchisserie-toulousaine-de-sante.com/sites/extranet.blanchisserie-toulousaine-de-sante.com/files/documents/justificatifs/vawutudujenopudup.pdfIn PDF document text
    • https://www.natsihwa.org.au/sites/default/files/webform/zolevijovexoneda.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/Uplcv/~3/1xuhb7AK25c/uplcv?utm_term=2nd+edition+dungeon+master+screen+downloadPDF link annotation
    • https://gradfutures.princeton.edu/system/files/webform/16157352895.pdfIn PDF document text
    • https://gradfutures.princeton.edu/system/files/webform/xafuzekimizitigemuseli.pdfIn PDF document text
    • https://lib.asu.edu/system/files/webform/bidemuf.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_off00014a94.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14A94 5388 bytes
SHA-256: a6eae8a85a384b2b1d5145e87177fb53cb7079cbdb73c4fe371b4335b24bee24
font_01_sfnt_off00015ce1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15CE1 11712 bytes
SHA-256: f5686ff62d9a3c7361c39b0080a6d1886f9b53b792b4b9de7583baa92bf75e1a