CVE-2026-59341
- Source
- https://cve.org/CVERecord?id=CVE-2026-59341
- Import Source
- https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-59341.json
- JSON Data
- https://api.osv.dev/v1/vulns/CVE-2026-59341
- Aliases
-
- GHSA-qj4p-m373-p2wg
- Published
- 2026-09-15T09:16:59Z
- Modified
- 2026-09-17T03:47:23Z
- Severity
-
- 4.2 (Medium) CVSS_V3 - CVSS:3.1/AV:N/AC:H/PR:H/UI:R/S:U/C:H/I:N/A:N CVSS Calculator
- Summary
- Sealed Secrets: decryption oracle via Go template injection in unauthenticated controller endpoints
- Details
-
A security vulnerability exists in the Sealed Secrets controller's unauthenticated POST endpoints. By submitting a modified payload containing custom Go template logic in spec.template.data, an attacker with internal network access can abuse the handler as a decryption oracle to recover the full plaintext of any sealed secret.
The POST /v1/verify and /v1/rotate handlers call Unseal() to decrypt target secrets, then render any Go templates found in spec.template.data.* using the decrypted payload as the evaluation context (pkg/apis/sealedsecrets/v1alpha1/sealedsecret_expansion.go). Errors encountered during template execution are directly reflected in the resulting HTTP response status codes.
Missing AEAD label binding: the spec.template.data field is omitted from the AEAD authenticated-data label binding ciphertext to metadata. As a result, an attacker can copy a target's valid metadata and encryptedData verbatim, satisfying AEAD decryption and label validation, while freely replacing spec.template.data with arbitrary template logic.
Side-channel oracle: template execution errors map directly to HTTP response codes. HTTP 200 (OK) indicates template execution succeeded; HTTP 409 (Conflict) indicates template execution failed (e.g. via {{ fail "..." }}).
By injecting conditional statements such as {{ if eq (substr 0 1 .password) "S" }}ok{{ else }}{{ fail "x" }}{{ end }}, an attacker receives an HTTP 200 status when a character guess is correct and an HTTP 409 when it is incorrect. This differential response leaks one character-equality bit per request, allowing full secret extraction over successive queries.
Attack vector & prerequisites: unauthenticated; requires network access to the controller's internal service port (:8080). Although this service is not exposed to the public internet by default, it is accessible to any pod within the Kubernetes cluster or via a kubectl port-forward connection.
- Database specific
{ "cna_assigner": "vmware", "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/59xxx/CVE-2026-59341.json" }- References