Malicious PDF — malware analysis report

Static analysis result for SHA-256 a5b7448a53e25f1d…

MALICIOUS

PDF

78.2 KB Created: 2021-04-07 08:22:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-05-26
MD5: e829cdc6e6d39c9da8ad95fbeca409bd SHA-1: c0825955f700b561cb64694c2b0b36531d9b0e5d SHA-256: a5b7448a53e25f1d9ed4299e73b89a27814432ffd01df48e8a9c035dc5bc603e
126 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many pointing to disposable domains, and exhibits characteristics of a link farm. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. Although no scripts were explicitly extracted, the PDF structure and embedded URIs suggest it's designed to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9962

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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
  • 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://ambrose.edu/sites/default/files/webform/20598750849.pdf In PDF document text
    • http://www.friendlycc.com/sites/default/files/webform/47778491084.pdfIn PDF document text
    • https://architecturaldesigninc.com/sites/default/files/56675633315.pdfIn PDF document text
    • https://extranet.blanchisserie-toulousaine-de-sante.com/sites/extranet.blanchisserie-toulousaine-de-sante.com/files/documents/justificatifs/pefusoxewirevujilo.pdfIn PDF document text
    • http://www.grotekeukens.be/sites/default/files/webform/gmawards2018/dakatiwilu.pdfIn PDF document text
    • http://seiary.com/sites/default/files/webform/rec/6045441545.pdfIn PDF document text
    • https://vectorcorp.net/sites/default/files/webform/resume/tefofavokalozigukar.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • http://feedproxy.google.com/~r/Uplcv/~3/YTWXjIUwRh0/uplcv?utm_term=vias+de+administracion+y+absorcion+de+farmacos+pdfPDF link annotation
    • https://drones.princeton.edu/system/files/webform/dovekilubexuvizufak.pdfIn PDF document text
    • https://minorsoncampus.princeton.edu/system/files/webform/45540448673.pdfIn PDF document text
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e46c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE46C 5264 bytes
SHA-256: 3eacf5310306c61cc5ec9029063cfffd2856eca90e7f0640183b2cee874da55a
font_01_sfnt_off0000f62f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF62F 11712 bytes
SHA-256: aff805bf65ddc8b67009d0dafe856e8877989f4ac51910f36598b6e23f5a0378
font_02_sfnt_off00011c50.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11C50 4324 bytes
SHA-256: 0d0f64e27578eb124b8bc81c7eceacdd166e22eddd95c81328e9fbd7de2a6333