How severe is CVE-2021-41230?

CVE-2021-41230 has a CVSS score of 8.8/10, rated HIGH. Immediate patching is strongly recommended.

Which packages are affected by CVE-2021-41230?

CVE-2021-41230 affects the following packages: github.com/pomerium/pomerium (Go). Ecosystems affected: Go.

How do I fix CVE-2021-41230?

Update github.com/pomerium/pomerium to 0.15.6 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2021-41230 is resolved across your whole dependency graph.

How do I detect CVE-2021-41230 in my Go dependencies?

Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for github.com/pomerium/pomerium, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.

How do I mitigate CVE-2021-41230 if there is no patch (or I can't update yet)?

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.

Is CVE-2021-41230 actively exploited in the wild?

No public exploit code has been indexed for CVE-2021-41230 yet. This does not mean the vulnerability cannot be exploited — absence of public exploits does not imply safety. Apply the recommended fix and use O3 Security to monitor your exposure.

What is the EPSS score for CVE-2021-41230?

CVE-2021-41230 has an EPSS (Exploit Prediction Scoring System) score of 0.9%, placing it in the 59th percentile of all CVEs. EPSS is maintained by FIRST.org and estimates the probability that a vulnerability will be exploited in the wild within the next 30 days. This score indicates relatively lower exploitation probability, though the CVSS severity should still guide your patching priority.

What type of vulnerability is CVE-2021-41230?

CVE-2021-41230 is classified as CWE-863 (CWE-863). This weakness type describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation.

When was CVE-2021-41230 published, and has it been updated?

CVE-2021-41230 was published on November 5, 2021 and was last updated on October 20, 2026. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

🐹

🐹 Go

Not in CISA KEV

HIGH severity

CVE-2021-41230 — pomerium

HIGHFix: pomerium/pomerium#2724

CVE-2021-41230 is a high-severity (CVSS 8.8) CWE-863 vulnerability in github.com/pomerium/pomerium. A fix is available for github.com/pomerium/pomerium — see the affected versions and patch details below.

OIDC claims not updated from Identity Provider in Pomerium

Also known asGHSA-j6wp-3859-vxfgGO-2021-0258

Published

Nov 5, 2021

Updated

Oct 20, 2026

Affected

1 pkg

Patched

1 / 1

Exploits

None indexed

Exploitation data as of Nov 7, 2026 · OSV.dev, NVD, FIRST.org (EPSS)

EPSS Exploitation Probability

via FIRST.org ↗

0.9%probability of exploitation in next 30 days

Lower Risk0.00%

Lower risk than most CVEs59th percentile — riskier than 59% of all scored CVEsHighest risk

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

1 pkg affected

🐹github.com/pomerium/pomerium

Real-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

Impact

Changes to the OIDC claims of a user after initial login are not reflected in policy evaluation when using allowed_idp_claims as part of policy. If using allowed_idp_claims and a user's claims are changed, Pomerium can make incorrect authorization decisions.

Patches

v0.15.6

Workarounds

Clear data on databroker service by clearing redis or restarting the in-memory databroker to force claims to be updated

References

https://github.com/pomerium/pomerium/pull/2724

For more information

If you have any questions or comments about this advisory:

Open an issue in Pomerium
Email us at [email protected]

Affected Packages

1 total 1 fixed

Ecosystem	Package	Vulnerable range	Fix
🐹Go	`github.com/pomerium/pomerium`	≥ 0.14.0&&< 0.15.6	0.15.6`go get github.com/pomerium/pomerium@v0.15.6`

Affected Products

1 product · 1 configurations

Application

pomeriumpomerium

≥ 0.14.0 && < 0.15.6

range

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for github.com/pomerium/pomerium, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update github.com/pomerium/pomerium to 0.15.6 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2021-41230 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

### Impact Changes to the OIDC claims of a user after initial login are not reflected in policy evaluation when using [`allowed_idp_claims`](https://www.pomerium.com/reference/#allowed-idp-claims) as part of policy. If using `allowed_idp_claims` and a user's claims are changed, Pomerium can make incorrect authorization decisions. ### Patches v0.15.6 ### Workarounds - Clear data on `databroker` service by clearing redis or restarting the in-memory databroker to force claims to be updated ### References https://github.com/pomerium/pomerium/pull/2724 ### For more information If you have any