Is CVE-2026-33757 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-33757 being exploited in the wild.

How severe is CVE-2026-33757?

Critical severity, with a CVSS score of 9.6, published 27 March 2026.

Which products and versions are affected?

github.com/openbao/openbao (Go) SEMVER:introduced=0,fixed=0.0.0-20260325142553-e32103951925; OpenBao < 2.5.2.

Is there a fix for CVE-2026-33757?

Yes. github.com/openbao/openbao (Go): upgrade to 0.0.0-20260325142553-e32103951925 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

How is CVE-2026-33757 attacked?

It is attacked over the network, in a hosted service.

Am I affected by CVE-2026-33757?

Check whether you run github.com/openbao/openbao (Go) or OpenBao at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2026-33757: OpenBao session fixation via OIDC direct callback mode

Q: Is there a fix for CVE-2026-33757?

Yes. github.com/openbao/openbao (Go): upgrade to 0.0.0-20260325142553-e32103951925 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

Q: How is CVE-2026-33757 attacked?

It is attacked over the network, in a hosted service.

Q: Am I affected by CVE-2026-33757?

Check whether you run github.com/openbao/openbao (Go) or OpenBao at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2026-33757 · Severity: critical · CVSS 9.6 · Published 2026-03-27

OpenBao is an open-source tool used by organizations to manage and protect sensitive information like passwords and encryption keys. A security flaw in its login process allows an attacker to trick a user into unintentionally authorizing a login session for the attacker. If successful, the attacker could gain full access to the victim's secrets and credentials, potentially leading to a total compromise of sensitive corporate data.

Technologies: github.com/openbao/openbao (Go), OpenBao. Vendors: Go, OpenBao.

Quick answers

Is CVE-2026-33757 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-33757 being exploited in the wild.
How severe is CVE-2026-33757?: Critical severity, with a CVSS score of 9.6, published 27 March 2026.
Which products and versions are affected?: github.com/openbao/openbao (Go) SEMVER:introduced=0,fixed=0.0.0-20260325142553-e32103951925; OpenBao < 2.5.2.
Is there a fix for CVE-2026-33757?: Yes. github.com/openbao/openbao (Go): upgrade to 0.0.0-20260325142553-e32103951925 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-33757 attacked?: It is attacked over the network, in a hosted service.
Am I affected by CVE-2026-33757?: Check whether you run github.com/openbao/openbao (Go) or OpenBao at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

How to fix

github.com/openbao/openbao (Go): upgrade to 0.0.0-20260325142553-e32103951925 or later
```
go get github.com/openbao/openbao@v0.0.0-20260325142553-e32103951925
```

Technical details

A session fixation vulnerability exists in OpenBao's JWT/OIDC authentication backend when a role is configured with `callback_mode` set to `direct`. The implementation lacks a manual confirmation step, allowing an attacker to initiate an authentication request and lure a victim to the verification URL. Because the `direct` mode communicates back to the API without user intervention, the attacker can poll the API until a token is issued to their own session upon the victim's successful authentication. This is a violation of the security considerations in RFC 8628 (OAuth 2.0 Device Authorization Grant). The vulnerability is resolved in version 2.5.2 by introducing a mandatory confirmation screen.

Affected products

OpenBao OpenBao < 2.5.2

Identifiers

CVE-2026-33757
GHSA-7q7g-x6vg-xpc3
GO-2026-4860

Timeline

2026-03-25: patched: Fix committed to repository
2026-03-27: disclosed: Initial advisory published

References

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