How severe is CVE-2026-33758?

CVE-2026-33758 has a CVSS 3.x base score of 6.1, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.

Is CVE-2026-33758 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (21st percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-33758?

CVE-2026-33758 affects Openbao. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-33758?

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

Does CVE-2026-33758 have an EU (EUVD) identifier?

Yes. CVE-2026-33758 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-16626.

When was CVE-2026-33758 published?

CVE-2026-33758 was published on 2026-03-27 and last updated on 2026-06-30.

CVE-2026-33758

CVE-2026-33758 is a medium-severity vulnerability in Openbao with a CVSS 3.x base score of 6.1. 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-20.

Key facts

Severity: Medium (CVSS 3.x base score 6.1)
CVSS v4: 9.4
EPSS exploit prediction: 0% (21st percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-16626
Weakness: CWE-20
Affected product: Openbao
Published: 2026-03-27
Last modified: 2026-06-30

Description

OpenBao is an open source identity-based secrets management system. Prior to version 2.5.2, OpenBao installations that have an OIDC/JWT authentication method enabled and a role with `callback_mode=direct` configured are vulnerable to XSS via the `error_description` parameter on the page for a failed authentication. This allows an attacker access to the token used in the Web UI by a victim. The `error_description` parameter has been replaced with a static error message in v2.5.2. The vulnerability can be mitigated by removing any roles with `callback_mode` set to `direct`.

Frequently asked questions

What is CVE-2026-33758?: OpenBao is an open source identity-based secrets management system. Prior to version 2.5.2, OpenBao installations that have an OIDC/JWT authentication method enabled and a role with `callback_mode=direct` configured are vulnerable to XSS via the `error_description` parameter on the page for a failed authentication. This allows an attacker access to the token used in the Web UI by a victim. The `error_description` parameter has been replaced with a static error message in v2.5.2. The vulnerability can be mitigated by removing any roles with `callback_mode` set to `direct`.
How severe is CVE-2026-33758?: CVE-2026-33758 has a CVSS 3.x base score of 6.1, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.
Is CVE-2026-33758 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (21st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-33758?: CVE-2026-33758 affects Openbao. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-33758?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2026-33758 have an EU (EUVD) identifier?: Yes. CVE-2026-33758 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-16626.
When was CVE-2026-33758 published?: CVE-2026-33758 was published on 2026-03-27 and last updated on 2026-06-30.

References

Affected products (1)

cpe:2.3:a:openbao:openbao:*:*:*:*:*:*:*:*

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