CVE-2026-33757: Github.com/openbao/openbao OpenBao Lacks User Confirmation For Vulnerability
CRITICALCVE-2026-33757 is a CRITICAL (CVSS 9.6) openbao lacks user confirmation for vulnerability (CWE-384: Session Fixation) affecting Github.com/openbao/openbao libraries in the Go ecosystem. The issue involves openbao lacks user confirmation for oidc direct callback mode. Remediation is available by upgrading affected packages to version 0.0.0-20260325142553-e32103951925.
CVE-2026-33757 at a Glance
Security Impact
CVSS: 9.6
The security impact metrics below are parsed directly from the CVSS v3.1 vector string (CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:L).
How to Fix CVE-2026-33757
To remediate this vulnerability, upgrade all affected Github.com/openbao/openbao dependencies to a patched release. Both direct and transitive dependencies should be checked, as frameworks or security libraries may pull in vulnerable versions transitively.
Upgrade github.com/openbao/openbao to 0.0.0-20260325142553-e32103951925Run the following command in your project directory to verify that all resolved dependencies use the patched release:
inspect dependencies for github.com/openbao/openbaoHow to Check if You Are Affected
To determine whether your application is affected by CVE-2026-33757, inspect your project dependencies for Github.com/openbao/openbao:
inspect dependencies for github.com/openbao/openbaoAnalyze the terminal output to locate any version of Github.com/openbao/openbao in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 0.0.0-20260325142553-e32103951925), your application is affected.
Note: Verify declared build manifests and deployed runtime container environments.
Technical Details
Vulnerability Mechanism & Technical Analysis
This vulnerability is classified under CWE-384: Session Fixation, where authenticating a user, or otherwise establishing a new user session, without invalidating any existing session identifier gives an attacker the opportunity to steal authenticated sessions. In Github.com/openbao/openbao, software state validation or input boundaries are circumvented during processing. Review the official source advisory statement below for specific affected components, classes, and reproduction details.
Source Advisory Statement
CVE-2026-33757 Affected Github.com/openbao/openbao Versions
1 component(s)| Product / Package | Ecosystem | Affected Versions | Fixed Version |
|---|---|---|---|
|
github.com/openbao/openbao
|
Go |
< 0.0.0-20260325142553-e32103951925
|
0.0.0-20260325142553-e32103951925
|
References
Frequently Asked Questions
What is CVE-2026-33757?
Which Github.com/openbao/openbao versions are affected?
What version fixes CVE-2026-33757?
Is github.com/openbao/openbao affected?
What is the CVSS score of CVE-2026-33757?
What CWE is associated with CVE-2026-33757?
How can I check Go dependencies for CVE-2026-33757?
Machine-readable OSV JSON
OSV v1.5 Schema
{
"schema_version" : "1.4.0",
"id" : "GHSA-7q7g-x6vg-xpc3",
"modified" : "2026-03-27T21:31:24Z",
"published" : "2026-03-26T18:32:54Z",
"aliases" : [ "CVE-2026-33757" ],
"summary" : "OpenBao lacks user confirmation for OIDC direct callback mode",
"details" : "### Impact\n\nOpenBao does not prompt for user confirmation when logging in via JWT/OIDC and a role with `callback_mode` set to `direct`.\n\nThis allows an attacker to start an authentication request and perform \"remote phishing\" by having the victim visit the URL and automatically log-in to the session of the attacker. Despite being based on the authorization code flow, the `direct` mode calls back directly to the API and allows an attacker to poll for an OpenBao token until it is issued.\n\n### Patches\nVersion 2.5.2 includes an additional confirmation screen for `direct` type logins that requires manual user interaction in order to finish the authentication.\n\n### Workarounds\nThis issue can be worked around either by removing any roles with `callback_mode=direct` or enforcing confirmation for every session on the token issuer side for the Client ID used by OpenBao.",
"severity" : [ {
"type" : "CVSS_V3",
"score" : "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:L"
} ],
"affected" : [ {
"package" : {
"ecosystem" : "Go",
"name" : "github.com/openbao/openbao"
},
"ranges" : [ {
"type" : "ECOSYSTEM",
"events" : [ {
"introduced" : "0"
}, {
"fixed" : "0.0.0-20260325142553-e32103951925"
} ]
} ]
} ],
"references" : [ {
"type" : "WEB",
"url" : "https://github.com/openbao/openbao/security/advisories/GHSA-7q7g-x6vg-xpc3"
}, {
"type" : "ADVISORY",
"url" : "https://nvd.nist.gov/vuln/detail/CVE-2026-33757"
}, {
"type" : "WEB",
"url" : "https://github.com/openbao/openbao/commit/e32103951925723e9787e33886ab6b6ec20f4964"
}, {
"type" : "WEB",
"url" : "https://datatracker.ietf.org/doc/html/rfc8628#section-5.4"
}, {
"type" : "PACKAGE",
"url" : "https://github.com/openbao/openbao"
} ],
"database_specific" : {
"cwe_ids" : [ "CWE-384" ],
"severity" : "CRITICAL",
"github_reviewed" : true,
"github_reviewed_at" : "2026-03-26T18:32:54Z",
"nvd_published_at" : "2026-03-27T15:16:57Z"
}
}