# CVE-2026-108126: temporal-proxy payload decryption is not bound to the request namespace

> CVE-2026-108126: temporal-proxy payload decryption is not bound to the request namespace. CVSS 6.0 (CVSS 4.0).

Canonical: https://rewindex.com/cve/CVE-2026-108126
Last updated: 2026-10-16T19:55:59Z

- Published: 2026-10-15 19:09 UTC · Updated: 2026-10-16 19:55 UTC · Assigner: Temporal
- CVSS: 6.0 (CVSS 4.0) · Severity: Medium
- EPSS: 0.36%, 29th percentile (scored 2026-10-25)
- CISA KEV: no
- CWE: CWE-639

## Description

temporal-proxy 0.2.0 through 0.8.0 does not bind encrypted payloads to the namespace they were encrypted for. When payload encryption is enabled, the proxy chooses the decryption key by an identifier stored in the payload rather than by the namespace of the request, and nothing in the ciphertext records that namespace. A caller whom the proxy authorizes only for namespace B, and who has obtained an encrypted payload from namespace A, can therefore have the proxy decrypt it. In 0.8.0, the caller can submit the payload to the codec server's /decode endpoint. In every affected version, a caller who can also write to namespace B on the Temporal server directly can place the payload there and read it back through the proxy. This holds whether namespaces share the default key or each has its own, because a single proxy holds every key it is configured with. The issue does not give the attacker encrypted payloads they could not already obtain, and does not allow encrypted payloads to be modified.

## Affected vendors and products

- Temporal Technologies, Inc.: temporal-proxy

## Tracked companies

- [Temporal Cloud](https://rewindex.com/company/temporal-cloud.md)

## References

- [CVE record on cve.org](https://www.cve.org/CVERecord?id=CVE-2026-108126)
- [NVD entry](https://nvd.nist.gov/vuln/detail/CVE-2026-108126)
- [https://github.com/temporalio/temporal-proxy/blob/v0.8.0/pkg/crypto/dek.go\#L54-L67](https://github.com/temporalio/temporal-proxy/blob/v0.8.0/pkg/crypto/dek.go#L54-L67)
- [https://github.com/temporalio/temporal-proxy/blob/v0.8.0/pkg/crypto/kek.go\#L172-L180](https://github.com/temporalio/temporal-proxy/blob/v0.8.0/pkg/crypto/kek.go#L172-L180)
- [https://github.com/temporalio/temporal-proxy/blob/v0.8.0/pkg/crypto/vault.go\#L256](https://github.com/temporalio/temporal-proxy/blob/v0.8.0/pkg/crypto/vault.go#L256)
- [https://github.com/temporalio/temporal-proxy/commit/508991c298b9ac31915dd7349ffa88d79fad3475](https://github.com/temporalio/temporal-proxy/commit/508991c298b9ac31915dd7349ffa88d79fad3475)
- [https://github.com/temporalio/temporal-proxy/commit/6843a2c4626aa2c7f00fbf54e4e9fa98f6254f07](https://github.com/temporalio/temporal-proxy/commit/6843a2c4626aa2c7f00fbf54e4e9fa98f6254f07)
- [https://github.com/temporalio/temporal-proxy/discussions/146](https://github.com/temporalio/temporal-proxy/discussions/146)
- [https://github.com/temporalio/temporal-proxy/pull/221](https://github.com/temporalio/temporal-proxy/pull/221)
- [https://github.com/temporalio/temporal-proxy/pull/222](https://github.com/temporalio/temporal-proxy/pull/222)
- [https://github.com/temporalio/temporal-proxy/releases/tag/v0.9.0](https://github.com/temporalio/temporal-proxy/releases/tag/v0.9.0)

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_Sources: CVE records from the CVE Program (cve.org). CVE® is a registered trademark of The MITRE Corporation. (https://www.cve.org/) This product uses data from the NVD API but is not endorsed or certified by the NVD. (https://nvd.nist.gov/) Known Exploited Vulnerabilities catalog from CISA. (https://www.cisa.gov/known-exploited-vulnerabilities-catalog) EPSS scores from FIRST (Exploit Prediction Scoring System). (https://www.first.org/epss/)_


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Canonical: https://rewindex.com/cve/CVE-2026-108126 · Markdown: https://rewindex.com/cve/CVE-2026-108126.md · JSON: https://rewindex.com/api/v1/cves/CVE-2026-108126 · Data licensed CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/) · Generated 2026-10-26T03:13:14.468Z