How severe is CVE-2025-4166?

CVE-2025-4166 has a CVSS 3.x base score of 4.5, rated medium severity. It is exploitable over network with low attack complexity, requires high privileges and user interaction. Impact on confidentiality is high, integrity none, and availability none.

Is CVE-2025-4166 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (25th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2025-4166?

CVE-2025-4166 primarily affects Hashicorp Vault. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2025-4166?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

Does CVE-2025-4166 have an EU (EUVD) identifier?

Yes. CVE-2025-4166 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-13240.

When was CVE-2025-4166 published?

CVE-2025-4166 was published on 2025-05-02 and last updated on 2026-06-17.

CVE-2025-4166

CVE-2025-4166 is a medium-severity vulnerability in Hashicorp Vault with a CVSS 3.x base score of 4.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-209.

Key facts

Severity: Medium (CVSS 3.x base score 4.5)
EPSS exploit prediction: 0% (25th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2025-13240
Weakness: CWE-209
Affected product: Hashicorp Vault
Published: 2025-05-02
Last modified: 2026-06-17

Description

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.

Frequently asked questions

What is CVE-2025-4166?: 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.
How severe is CVE-2025-4166?: CVE-2025-4166 has a CVSS 3.x base score of 4.5, rated medium severity. It is exploitable over network with low attack complexity, requires high privileges and user interaction. Impact on confidentiality is high, integrity none, and availability none.
Is CVE-2025-4166 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (25th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2025-4166?: CVE-2025-4166 primarily affects Hashicorp Vault. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2025-4166?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2025-4166 have an EU (EUVD) identifier?: Yes. CVE-2025-4166 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-13240.
When was CVE-2025-4166 published?: CVE-2025-4166 was published on 2025-05-02 and last updated on 2026-06-17.

References

https://discuss.hashicorp.com/t/hcsec-2025-09-vault-may-expose-sensitive-information-in-error-logs-when-processing-malformed-data-with-the-kv-v2-plugin

Affected products (3)

cpe:2.3:a:hashicorp:vault:*:*:*:*:enterprise:*:*:*
cpe:2.3:a:hashicorp:vault:*:*:*:*:-:*:*:*
cpe:2.3:a:openbao:openbao:*:*:*:*:*:*:*:*

More vulnerabilities in Hashicorp Vault

CVE-2020-35192 — Critical (CVSS 9.8): The official vault docker images before 0.11.6 contain a blank password for a root user. System using the vault docker…
CVE-2020-12757 — Critical (CVSS 9.8): HashiCorp Vault and Vault Enterprise 1.4.0 and 1.4.1, when configured with the GCP Secrets Engine, may incorrectly…
CVE-2025-6000 — Critical (CVSS 9.1): A privileged Vault operator within the root namespace with write permission to {{sys/audit}} may obtain code execution…
CVE-2022-40186 — Critical (CVSS 9.1): An issue was discovered in HashiCorp Vault and Vault Enterprise before 1.11.3. A vulnerability in the Identity Engine…
CVE-2022-36129 — Critical (CVSS 9.1): HashiCorp Vault Enterprise 1.7.0 through 1.9.7, 1.10.4, and 1.11.0 clusters using Integrated Storage expose an…
CVE-2020-10661 — Critical (CVSS 9.1): HashiCorp Vault and Vault Enterprise versions 0.11.0 through 1.3.3 may, under certain circumstances, have existing…

All CVEs affecting Hashicorp Vault →

Other CWE-209 (Generation of Error Message Containing Sensitive Information) vulnerabilities

CVE-2025-62168 — Critical (CVSS 10.0): Squid is a caching proxy for the Web. In Squid versions prior to 7.2, a failure to redact HTTP authentication…
CVE-2025-68110 — Critical (CVSS 9.9): ChurchCRM is an open-source church management system. Versions prior to 6.5.3 may disclose database information in an…
CVE-2025-46658 — Critical (CVSS 9.8): An issue was discovered in ExonautWeb in 4C Strategies Exonaut 21.6. There are verbose error messages.
CVE-2024-28285 — Critical (CVSS 9.8): A Fault Injection vulnerability in the SymmetricDecrypt function in cryptopp/elgamal.h of Cryptopp Crypto++ 8.9, allows…
CVE-2023-40767 — Critical (CVSS 9.8): User enumeration is found in in PHPJabbers Make an Offer Widget v1.0. This issue occurs during password recovery, where…
CVE-2023-40766 — Critical (CVSS 9.8): User enumeration is found in in PHPJabbers Ticket Support Script v3.2. This issue occurs during password recovery,…

Browse all CWE-209 (Generation of Error Message Containing Sensitive Information) vulnerabilities →