CVE-2025-4166 | Vault May Include Sensitive Data in Error Logs When Using the KV v2 Plugin

Vault Community and Vault Enterprise Key/Value (kv) Version 2 plugin may unintentionally expose sensitive information in server and audit logs when users submit malformed payloads during secret creation or update operations via the Vault REST API. This vulnerability, identified as CVE-2025-4166, is fixed in Vault Community 1.19.3 and Vault Enterprise 1.19.3, 1.18.9, 1.17.16, 1.16.20.

Published: 2025-05-02 Last update: 2025-12-31 Assigner: [email protected] Source: [email protected]
NVD Status：Analyzed，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2025-4166 is rated Low Risk (30.1/100): CVSS Medium severity, with low exploitation likelihood (EPSS 0.15%). Monitor for updates and reassess as exploit intelligence or EPSS changes.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2025-4166

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-05-27 0.18% 0.15% -0.04%
2 2026-05-25 0.15% 0.18% +0.04%
3 2026-02-26 — 0.15% —

Full EPSS history (6 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2025-4166

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
4.5 3.1 MEDIUM
CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:U/C:H/I:N/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:H)
They need powerful rights—admin, root, or similar—before this pays off.
User interaction (UI:R)
A real person has to do something—click, install, enable—otherwise it doesn’t land.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:N)
Service keeps running; no real outage angle.
 0.9 3.6 [email protected]
6.5 3.1 MEDIUM
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:R)
A real person has to do something—click, install, enable—otherwise it doesn’t land.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:N)
Service keeps running; no real outage angle.
 2.8 3.6 [email protected]

Weakness enumeration for CVE-2025-4166

GitHub Security Advisory for CVE-2025-4166

GHSA-gcqf-f89c-68hv · Severity: medium · Ecosystem: go — Hashicorp Vault Community vulnerable to Generation of Error Message Containing Sensitive Information

OS Trackers for CVE-2025-4166

vendor priority summary link
alpine — CVE-2025-4166: 2 source package rows (openbao, vault); 13 state rows across 2 repos (3.22-community, edge-community); fixed 2, open 11. https://security.alpinelinux.org/vuln/CVE-2025-4166
redhat medium — https://access.redhat.com/security/cve/CVE-2025-4166
suse medium — https://www.suse.com/security/cve/CVE-2025-4166/

Affected software / configurations for CVE-2025-4166

Vendor Product Version Raw CPE
hashicorp vault >= 0.3.0, < 1.16.20 cpe:2.3:a:hashicorp:vault:*:*:*:*:enterprise:*:*:*
hashicorp vault >= 0.3.0, < 1.19.3 cpe:2.3:a:hashicorp:vault:*:*:*:*:-:*:*:*
hashicorp vault >= 1.17.0, < 1.17.16 cpe:2.3:a:hashicorp:vault:*:*:*:*:enterprise:*:*:*
hashicorp vault >= 1.18.0, < 1.18.9 cpe:2.3:a:hashicorp:vault:*:*:*:*:enterprise:*:*:*
hashicorp vault >= 1.19.0, < 1.19.3 cpe:2.3:a:hashicorp:vault:*:*:*:*:enterprise:*:*:*
openbao openbao < 2.2.2 cpe:2.3:a:openbao:openbao:*:*:*:*:*:*:*:*

References for CVE-2025-4166

cvelogic Threat Intelligence