# CVE-2026-50565: Fission privilege escalation via ServiceAccount token automount in builder pods

Source: https://junglewise.ai/threats/cve-2026-50565-fission-privilege-escalation-via-serviceaccount-token-automount  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-06-10. Updated: 2026-06-30  
License: CC BY 4.0 with a link back

CVE-2026-50565 · Severity: medium · CVSS 4.9 · Published 2026-06-10

Fission, an open-source serverless framework for Kubernetes, was found to automatically share sensitive security credentials with user-provided code during the build process. An attacker with the ability to create or update environments could use these credentials to access all secrets and configuration data within the builder's workspace. This could lead to the exposure of sensitive information such as API keys, passwords, and internal configuration details.

Technologies: [Fission](https://junglewise.ai/threats/technologies/fission), [github.com/fission/fission (Go)](https://junglewise.ai/threats/technologies/github-com-fission-fission). Vendors: [Fission](https://junglewise.ai/threats/vendors/fission), [Go](https://junglewise.ai/threats/vendors/go).

## Quick answers

**Is CVE-2026-50565 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-50565 being exploited in the wild.

**How severe is CVE-2026-50565?** Medium severity, with a CVSS score of 4.9, published 10 June 2026.

**Which products and versions are affected?** Fission <= 1.23.0; github.com/fission/fission (Go) <= 1.23.0, SEMVER:introduced=0,fixed=1.24.0.

**Is there a fix for CVE-2026-50565?** Yes. github.com/fission/fission (Go): upgrade to 1.24.0 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-50565 attacked?** It is attacked over the network, in a software library.

**Am I affected by CVE-2026-50565?** Check whether you run Fission or github.com/fission/fission (Go) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## How to fix

- github.com/fission/fission (Go): upgrade to 1.24.0 or later

  ```sh
  go get github.com/fission/fission@v1.24.0
  ```


## Technical details

Fission builder pods were created using the 'fission-builder' ServiceAccount without explicitly disabling the 'AutomountServiceAccountToken' setting. Because users can control the builder container image and podspec via Environment CRDs, any code executed within the builder container inherits the 'fission-builder' identity. This ServiceAccount possesses namespace-wide 'get' permissions for secrets and configmaps. An attacker with 'create' or 'update' permissions on Environment CRDs can exploit this to read all sensitive data in the builder namespace. The issue was addressed in version 1.24.0 by disabling token automounting and using projected volumes for the fetcher sidecar only.

## Affected products

- fission fission <= 1.23.0

## Identifiers

- CVE-2026-50565
- GHSA-8wcj-mfrc-jx5q
- GO-2026-5850

## Timeline

- 2026-05-26: disclosed: Initial report to Fission
- 2026-06-10: advisory: NVD publication date
- 2026-06-30: patched: GitHub Advisory published and fix confirmed in v1.24.0

## References

- [https://api.github.com/users/tonghuaroot](https://api.github.com/users/tonghuaroot)
- [https://github.com/tonghuaroot](https://github.com/tonghuaroot)
- [https://api.github.com/users/tonghuaroot/gists%7B/gist_id%7D](https://api.github.com/users/tonghuaroot/gists%7B/gist_id%7D)
- [https://api.github.com/users/tonghuaroot/repos](https://api.github.com/users/tonghuaroot/repos)
- [https://avatars.githubusercontent.com/u/23011166?v=4](https://avatars.githubusercontent.com/u/23011166?v=4)
- [https://api.github.com/users/tonghuaroot/events%7B/privacy%7D](https://api.github.com/users/tonghuaroot/events%7B/privacy%7D)

## Related threats

- [GO-2026-5849 - Fission: MessageQueueTrigger scaler manager materializes Secret values into Deployment envvars and accepts arbitrary user PodSpec in github.](https://junglewise.ai/threats/go-2026-5849-fission-messagequeuetrigger-scaler-manager-materializes-509f5f41)
- [Fission privilege escalation in MessageQueueTrigger scaler manager](https://junglewise.ai/threats/fission-privilege-escalation-in-messagequeuetrigger-scaler-manager-7fe266a4)
- [Fission incomplete capability denylist in Environment and Function CRDs](https://junglewise.ai/threats/cve-2026-50570-fission-incomplete-capability-denylist-in-environment-and)
- [Fission HTTPTrigger improper input validation in RelativeURL and Prefix](https://junglewise.ai/threats/cve-2026-50569-fission-httptrigger-improper-input-validation-in-relativeurl-and)
- [Fission path traversal in SanitizeFilePath utility](https://junglewise.ai/threats/cve-2026-50568-fission-path-traversal-in-sanitizefilepath-utility)