---
id: CVE-2026-15638
title: >-
  An unauthenticated user with access to Secret Server could leverage a padding
  oracle to decrypt or encrypt data using one of the server's cryptographic keys
summary: >-
  An unauthenticated user with access to Secret Server could leverage a padding
  oracle to decrypt or encrypt data using one of the server's cryptographic
  keys. The key itself is not exposed.
severity: critical
cvss: 9.1
cvssVector: 'CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:H/VI:L/VA:N/SC:H/SI:H/SA:H'
cwe:
  - CWE-327
vendor: Delinea
product: Secret Server (On-Prem)
affected:
  - secret_server_on-prem >= 10.5.1 <= 12.1.3
published: '2026-09-16'
updated: '2026-09-18'
sourceUpdated: '2026-09-18T19:34:36.657'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-15638'
references:
  - url: 'https://delinea.com/security-advisories'
    label: 1443cd92-d354-46d2-9290-d812316ca43a
tags:
  - nvd
  - cve.org
epss: 0.00201
epssPercentile: 0.08913
ssvc:
  exploitation: none
  automatable: 'no'
  technicalImpact: total
  timestamp: '2026-09-16T19:36:39.986689Z'
cvssSource: cna
ingestedAt: '2026-09-15T23:46:25.572Z'
---

## Overview

An unauthenticated user with access to Secret Server could leverage a padding oracle to decrypt or encrypt data using one of the server's cryptographic keys. The key itself is not exposed.

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.