Your RSA-2048 keys break in 2030. Find every one of them before attackers do.
📦
📦 npm
Not in CISA KEV
HIGH severity

CVE-2021-41246 — express-openid-connect

HIGHFix: auth0/express-openid-connect@5ab67ff

CVE-2021-41246 is a high-severity (CVSS 8.8) CWE-384 vulnerability in express-openid-connect. A fix is available for express-openid-connect — see the affected versions and patch details below.

Session fixation in express-openid-connect

Also known asGHSA-7rg2-qxmf-hhx9
Published
Updated
Affected
1 pkg
Patched
1 / 1
Exploits
None indexed
Exploitation data as of Oct 7, 2026 · OSV.dev, NVD, FIRST.org (EPSS)

EPSS Exploitation Probability

via FIRST.org ↗
0.9%probability of exploitation in next 30 days
Lower Risk+0.03%
Lower risk than most CVEs59th percentile — riskier than 59% of all scored CVEsHighest risk
0.00%0.47%0.95%1.42%0.4%0.9%Apr 26Aug 26Oct 26

Probability of exploitation in the next 30 days, from FIRST.org EPSS.

How urgent is this, really

CVE-2021-41246 by exploitation likelihood (EPSS) against impact (CVSS). Outside the shaded patch-first corner.

Where this sits among everything scored

Of 385,738 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Counts from FIRST.org, log-scaled.

Real-World Exposure

1 pkg affected

How broadly this vulnerability is actually deployed: weekly install volume shows current usage, and reverse-dependency count shows how many other packages break if it stays unpatched.

56other npm packages depend on this — each one inherits the vulnerability until it's patched upstream
express-openid-connectnpm
199Kdownloads / week

Description

Overview

Versions 2.3.0 up to and including 2.5.1 do not regenerate the session id and session cookie when user logs in. This behavior opens up the application to various session fixation vulnerabilities.

Am I affected?

You are affected by this vulnerability if you are using express-openid-connect version 2.3.0 up to and including 2.5.1 and use a custom session store.

How to fix that?

Upgrade to version >= 2.5.2.

Will this update impact my users?

The fix provided in patch will not affect your users.

Affected Packages

1 total 1 fixed
EcosystemPackageVulnerable rangeFix
📦npmexpress-openid-connect≥ 2.3.0&&< 2.5.22.5.2npm install express-openid-connect@2.5.2

Affected Products

1 product · 1 configurations
Application
express openid connectauth0
≥ 2.3.0 && < 2.5.2
range

Detection & mitigation playbook

Open-source dependency

  1. Detect

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

  2. Fix

    Update express-openid-connect to 2.5.2 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2021-41246 is resolved across your whole dependency graph.

  3. 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

### Overview Versions `2.3.0` up to and including `2.5.1` do not regenerate the session id and session cookie when user logs in. This behavior opens up the application to various session fixation vulnerabilities. ### Am I affected? You are affected by this vulnerability if you are using `express-openid-connect` version `2.3.0` up to and including `2.5.1` and use a custom session store. ### How to fix that? Upgrade to version `>= 2.5.2`. ### Will this update impact my users? The fix provided in patch will not affect your users.
O3 Security · Impact-Aware SCA

Is CVE-2021-41246 in your dependencies?

Find it across npm, including transitive dependencies.

Scan my dependencies How O3 SCA works
CVE-2021-41246: express-openid-connect — Fixed in 2.5.2