# CVE-2026-123802: SuperTokens Core is an open source authentication server.


- **Severity:** High 8.1 (`CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N`)
- **Exploited in the wild:** Not known
- **Fix available:** No
- **Published:** 9 Nov 2026
- **Updated:** 9 Nov 2026
- **Also known as:** GHSA-wfg2-vqfg-rqh6

## What is CVE-2026-123802?

CVE-2026-123802 is a high-severity vulnerability in supertokens-core, published on 9 Nov 2026. 

### Official description

SuperTokens Core is an open source authentication server. From 11.3.0 until 11.3.8, 11.4.8, 12.0.11, 12.1.2, 12.2.1, and 12.3.1, a licensed deployment with a configured SAML client can authenticate an identity from an assertion that did not satisfy the audience check. When the identity provider uses assertion-level signing, an attacker who has a still-valid IdP-signed assertion naming the victim for any audience and the attacker's own valid assertion for the target audience can combine them because validateSamlResponseAudience accepts an audience from one assertion while extractAllClaims takes the final NameID and attributes from another; response-level signing does not expose this multi-assertion variant. Independently, an assertion from an identity provider configured for the target deployment but issued to another SuperTokens deployment using the shared default saml_sp_entity_id can satisfy the target's audience check. Successful exploitation authenticates the attacker as the victim IdP user. This issue is fixed in versions 11.3.8, 11.4.8, 12.0.11, 12.1.2, 12.2.1, and 12.3.1.

Weakness: CWE-345 (Insufficient Verification of Data Authenticity), CWE-287 (Improper Authentication), CWE-1220 (Insufficient Granularity of Access Control)

## Which versions are affected by CVE-2026-123802?


## How do I fix CVE-2026-123802?

No fix has been published for CVE-2026-123802 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-123802 being exploited?

There is no known exploitation of CVE-2026-123802 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-123802 and fix it if it is affected.

What it is: CVE-2026-123802 is a high-severity vulnerability in supertokens-core, published on 9 Nov 2026. 
Exploitation: There is no known exploitation of CVE-2026-123802 in the wild and no public exploit code.

Affected product: supertokens-core. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-123802/ (Markdown: https://insights.sbomify.com/CVE-2026-123802/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-123802
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-123802
- OSV: https://osv.dev/vulnerability/CVE-2026-123802

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-123802/
Summaries are generated and may contain mistakes; the official description above is the record.