---
id: CVE-2026-78403
title: Unauthenticated Stack Buffer Overflow in Sentinel Keys Server
summary: |-
  Stack-based buffer overflow and missing
  authorization vulnerability in Thales Sentinel Keys Server on Windows allows
  Overflow Buffers. Sentinel Keys Server does not check the length of the first
  field in the HTTP request. An attacker may…
severity: critical
cvss: 9.8
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H'
cvssSource: cna
cwe:
  - CWE-121
  - CWE-862
vendor: Thalesgroup
product: Sentinel Keys Server
affected:
  - sentinel_keys_server < 1.3.8.0
ssvc:
  exploitation: none
  automatable: 'yes'
  technicalImpact: total
  timestamp: '2026-10-30T19:59:29.771309Z'
published: '2026-10-30'
updated: '2026-10-30'
sourceUpdated: '2026-10-30T20:02:33.210Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2026-78403'
references:
  - url: >-
      https://supportportal.thalesgroup.com/csm?id=kb_article_view&sys_kb_id=50fc9f3b3b005f10bba8b41864e45a61&sysparm_article=KB0031216
tags:
  - cve.org
epss: 0.00577
epssPercentile: 0.4766
ingestedAt: '2026-11-05T16:24:31.446Z'
---

## Overview

Stack-based buffer overflow and missing
authorization vulnerability in Thales Sentinel Keys Server on Windows allows
Overflow Buffers. Sentinel Keys Server does not check the length of the first
field in the HTTP request. An attacker may craft an HTTP request and send it to
Sentinel Keys Server. It may lead to remote code execution as NT
AUTHORITY\SYSTEM.





This issue affects Sentinel Keys Server:
versions lower than 1.3.8.0.

## Affected

- `sentinel_keys_server < 1.3.8.0`

## Remediation

Upgrade to latest version.