CVE-2026-33495 is a medium-severity (CVSS 6.5) CWE-862 vulnerability in github.com/ory/oathkeeper. A fix is available for github.com/ory/oathkeeper — see the affected versions and patch details below.
Ory Oathkeeper has an authentication bypass by usage of untrusted header
Exploitation Status
No confirmed exploitation observed yet
- CISA assesses this as automatable — exploitation doesn’t require manual, per-target effort, which raises the odds of mass scanning and opportunistic attacks.
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for CVE-2026-33495.
EPSS Exploitation Probability
Probability of exploitation in the next 30 days, from FIRST.org EPSS.
How urgent is this, really
Where this sits among everything scored
Real-World Exposure
github.com/ory/oathkeeperReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects Go packages — download data is not available via public APIs for these ecosystems.
Description
ORY Oathkeeper is an Identity & Access Proxy (IAP) and Access Control Decision API that authorizes HTTP requests based on sets of Access Rules. Ory Oathkeeper is often deployed behind other components like CDNs, WAFs, or reverse proxies. Depending on the setup, another component might forward the request to the Oathkeeper proxy with a different protocol (http vs. https) than the original request. In order to properly match the request against the configured rules, Oathkeeper considers the X-Forwarded-Proto header when evaluating rules. The configuration option serve.proxy.trust_forwarded_headers (defaults to false) governs whether this and other X-Forwarded-* headers should be trusted. Prior to version 26.2.0, Oathkeeper did not properly respect this configuration, and would always consider the X-Forwarded-Proto header. In order for an attacker to abuse this, an installation of Ory Oathkeeper needs to have distinct rules for HTTP and HTTPS requests. Also, the attacker needs to be able to trigger one but not the other rule. In this scenario, the attacker can send the same request but with the X-Forwarded-Proto header in order to trigger the other rule. We do not expect many configurations to meet these preconditions. Version 26.2.0 contains a patch. Ory Oathkeeper will correctly respect the serve.proxy.trust_forwarded_headers configuration going forward, thereby eliminating the attack scenario. We recommend upgrading to a fixed version even if the preconditions are not met. As an additional mitigation, it is generally recommended to drop any unexpected headers as early as possible when a request is handled, e.g. in the WAF.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐹Go | github.com/ory/oathkeeper | all versions | 0.40.10-0.20260320084810-e9acca14a04dgo get github.com/ory/oathkeeper@v0.40.10-0.20260320084810-e9acca14a04d |
Affected Products
oathkeeperoryDetection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for github.com/ory/oathkeeper, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update github.com/ory/oathkeeper to 0.40.10-0.20260320084810-e9acca14a04d or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-33495 is resolved across your whole dependency graph.
Workarounds
Put an independent control in front of the weakness: restrict the affected endpoint or interface to trusted networks, require an additional authentication factor or proxy-level check, and invalidate existing sessions and credentials in case the flaw has already been used.
Frequently Asked Questions
Is CVE-2026-33495 in your dependencies?
Find it across Go, including transitive dependencies.