Malicious PDF — malware analysis report

Static analysis result for SHA-256 441740f90c740c40…

MALICIOUS

PDF

67.7 KB Created: 2021-04-25 18:47:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-05-29
MD5: 2c80c2d5b0e4cdca7d4dd0f4768d8558 SHA-1: 018b1b42887b645b32c2aab52696ba787dd87ea6 SHA-256: 441740f90c740c40a07743d7590b0504cdbd57d4428553c3197201f856ca51ee
126 Risk Score

Malware Insights

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

This PDF file was flagged by ML classifiers and ClamAV as malicious, indicating a phishing or trojan distribution attempt. The document body, though heavily obfuscated, contains references to teaching ideas, likely a lure to encourage clicks on embedded links. The numerous external URIs, many pointing to link farms, suggest an attempt to redirect users to malicious sites or download further payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://www.osgeurope.com/sites/osg-corporate.dev/files/webform/gurasijam.pdf In PDF document text
    • http://www.grotekeukens.be/sites/default/files/webform/gmawards2018/dufadurelabakugozuku.pdfIn PDF document text
    • https://www.jsif.org/sites/default/files/webform/rijuluzevowogadabiwi.pdfIn PDF document text
    • https://www.a1touchsolution.nl/sites/default/files/wozupidojenebimovom.pdfIn PDF document text
    • http://portal-mysigma.com/system/files/student-proof/woximinel.pdfIn PDF document text
    • https://vectorcorp.net/sites/default/files/webform/resume/sowasipaxezok.pdfIn PDF document text
    • http://oaklandchildcare.org/sites/default/files/webform/bidepe.pdfIn PDF document text
    • https://www.enwidth.com/sites/default/files/webform/resumes/21555212736.pdfIn PDF document text
    • https://www.mothercare.ro/sites/default/files/webform/resumes/tizagoge.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/zMnd8XtcwSM/uplcv?utm_term=simile+and+metaphor+teaching+ideasPDF link annotation
    • https://www.ice.cam.ac.uk/sites/www.ice.cam.ac.uk/files/webform/wosevojowavinojefe.pdfIn PDF document text
    • https://lib.asu.edu/system/files/webform/bidemuf.pdfIn PDF document text
    • https://lib.asu.edu/system/files/webform/liwubuwivak.pdfIn PDF document text
    • https://printandmail.princeton.edu/system/files/webform/83401752781.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 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000cc0b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCC0B 5592 bytes
SHA-256: 4aea326484279f693d68ba73302634eea3363e6f9520c15a98701c12b1449d66
font_01_sfnt_off0000deda.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDEDA 10772 bytes
SHA-256: 433a7fe2e29fe2408ca7b87e6a84a11706bbb8891a713bf7ea46f9ca4c24675e