Malicious PDF — malware analysis report

Static analysis result for SHA-256 423273e2a8f80cbc…

MALICIOUS

PDF

69.0 KB Created: 2021-04-21 14:09:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-04
MD5: 8749ea2527ce7f372d4c553204f4ff9e SHA-1: 5e2afbaab715d8e327f90a4b5695d679550825e0 SHA-256: 423273e2a8f80cbc89e99d266918156202195bafdaca3d9bfe40b702877af5e4
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 5

  • 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
  • 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 http://spotlight-sites.com/sites/default/files/webform/wokasonexigugeb.pdf In PDF document text
    • https://ambrose.edu/sites/default/files/webform/sudelo.pdfIn PDF document text
    • https://www.enwidth.com/sites/default/files/webform/resumes/fudigebifofonixetizitalu.pdfIn PDF document text
    • https://www.dgs-interparts.be/sites/default/files/36138637258.pdfIn PDF document text
    • http://spotlight-sites.com/sites/default/files/webform/93789740410.pdfIn PDF document text
    • https://www.mothercare.ro/sites/default/files/webform/resumes/susumijifiwef.pdfIn PDF document text
    • https://www.blplegal.com/sites/default/files/webform/3097059720.pdfIn PDF document text
    • http://www.muttypawsacademy.com/sites/default/files/webform/vaccines/nojezajewi.pdfIn PDF document text
    • https://www.blplegal.com/sites/default/files/webform/54305505708.pdfIn PDF document text
    • https://www.termis.org/system/files/webform/manejuwavujegajejumoxak.pdfIn PDF document text
    • https://www.osgeurope.com/sites/osg-corporate.dev/files/webform/19824824677.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/cv9VXjIrmdE/uplcv?utm_term=how+to+teach+totin+chipPDF link annotation
    • https://www.healthdata.org/sites/default/files/resumes/jojilekavoxojomoz.pdfIn PDF document text
    • https://www.healthdata.org/sites/default/files/resumes/sutuzosugogaw.pdfIn PDF document text
    • https://drones.princeton.edu/system/files/webform/vijebutipide.pdfIn PDF document text
    • https://drones.princeton.edu/system/files/webform/66931006591.pdfIn PDF document text
    • https://printandmail.princeton.edu/system/files/webform/31356988355.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_off0000d4ef.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD4EF 4768 bytes
SHA-256: 79a6d322ffa3fd18d0ca889b5360cf43d58b04530f69937b037d076aedf8dd34
font_01_sfnt_off0000e538.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE538 10044 bytes
SHA-256: 128fc451dbbfc4a711e69cf3882b02a9f3133c05d10fe8632fd7ff82df692014