---
id: CVE-2026-108126
title: >-
  temporal-proxy 0.2.0 through 0.8.0 does not bind encrypted payloads to the
  namespace they were encrypted for
summary: >-
  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 …
severity: medium
cvss: 6
cvssVector: 'CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N'
cwe:
  - CWE-639
vendor: 'Temporal Technologies, Inc.'
product: github.com/temporalio/temporal-proxy
affected:
  - github.com/temporalio/temporal-proxy >= 0.2.0 < 0.9.0
published: '2026-10-15'
updated: '2026-10-15'
sourceUpdated: '2026-10-15T19:17:19.873'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-108126'
references:
  - url: >-
      https://github.com/temporalio/temporal-proxy/blob/v0.8.0/pkg/crypto/dek.go#L54-L67
    label: security@temporal.io
  - url: >-
      https://github.com/temporalio/temporal-proxy/blob/v0.8.0/pkg/crypto/kek.go#L172-L180
    label: security@temporal.io
  - url: >-
      https://github.com/temporalio/temporal-proxy/blob/v0.8.0/pkg/crypto/vault.go#L256
    label: security@temporal.io
  - url: >-
      https://github.com/temporalio/temporal-proxy/commit/508991c298b9ac31915dd7349ffa88d79fad3475
    label: security@temporal.io
  - url: >-
      https://github.com/temporalio/temporal-proxy/commit/6843a2c4626aa2c7f00fbf54e4e9fa98f6254f07
    label: security@temporal.io
  - url: 'https://github.com/temporalio/temporal-proxy/discussions/146'
    label: security@temporal.io
  - url: 'https://github.com/temporalio/temporal-proxy/pull/221'
    label: security@temporal.io
  - url: 'https://github.com/temporalio/temporal-proxy/pull/222'
    label: security@temporal.io
  - url: 'https://github.com/temporalio/temporal-proxy/releases/tag/v0.9.0'
    label: security@temporal.io
tags:
  - nvd
  - cve.org
cvssSource: cna
ingestedAt: '2026-10-15T19:25:46.397Z'
ssvc:
  exploitation: none
  automatable: 'no'
  technicalImpact: partial
  timestamp: '2026-10-15T20:04:10.335323Z'
---

## Overview

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.

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.