Malicious PDF — malware analysis report

Static analysis result for SHA-256 c83aefb35f36360a…

MALICIOUS

PDF

88.7 KB Created: 2021-04-06 21:08:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-18
MD5: 847dc76ec660e93cc6bde2273c6ff135 SHA-1: 8c192e86827fe52eb076d8144c65286757c8c3f4 SHA-256: c83aefb35f36360a592532ffa4c31450f63bd806e1bc0bbdc09cb183bfd40264
124 Risk Score

Malware Insights

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

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics identified it as a link farm on disposable hosting, suggesting a phishing or malware distribution scheme. Although no scripts were explicitly extracted, the PDF structure and embedded URLs point towards an attempt to redirect users to malicious sites, likely for further exploitation.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9787

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://www.muttypawsacademy.com/sites/default/files/webform/vaccines/17184396690.pdf In PDF document text
    • http://www.pbttphtk.gov.my/sites/default/files/webform/42283273604.pdfIn PDF document text
    • https://www.cdcplumbing.com/sites/default/files/webform/contact-us/65589142167.pdfIn PDF document text
    • https://www.enwidth.com/sites/default/files/webform/resumes/21555212736.pdfIn PDF document text
    • https://grossenbacher.co.nz/en/system/files/avoidance-training-certificates/bekam.pdfIn PDF document text
    • https://grossenbacher.co.nz/en/system/files/avoidance-training-certificates/95133977644.pdfIn PDF document text
    • http://www.guninetwork.org/system/files/webform/heirri_proposals/wozat.pdfIn PDF document text
    • http://www.pacificsportfraservalley.com/sites/default/files/webform/zajufofagobixipisuna.pdfIn PDF document text
    • https://web.liderpapel.com/sites/default/files/webform/xikamiwaboloz.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
    • http://oaklandchildcare.org/sites/default/files/webform/wafawujozovu.pdfIn PDF document text
    • https://ambrose.edu/sites/default/files/webform/11118021720.pdfIn PDF document text
    • https://www.uts.cw/sites/default/files/webform/50818196885.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://feedproxy.google.com/~r/Uplcv/~3/ngfLrbzwjls/uplcv?utm_term=denon+avr-+x3300w+manual+pdfPDF link annotation
    • https://ubmemeaensoprod.s3.amazonaws.com/ifsec_international/call_for_papers/2021/03/woragirewun.pdfIn PDF document text
    • https://www.vub.be/sites/vub/files/webform/rifavuzido.pdfIn PDF document text
    • https://lib.asu.edu/system/files/webform/53252105934.pdfIn PDF document text
    • http://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00014fc7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14FC7 5564 bytes
SHA-256: 0d563513795d91e14177928eae1a5ee3000486746770ef5017d577a4751a5692