# CVE-2026-49820: Probo open redirect bypass via path normalization in saferedirect

Source: https://junglewise.ai/threats/cve-2026-49820-probo-open-redirect-bypass-via-path-normalization-in-saferedirect  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-08-13. Updated: 2026-06-30  
License: CC BY 4.0 with a link back

CVE-2026-49820 · Severity: medium · CVSS 4.7 · Published 2026-08-13

Probo, a platform used for authentication and session management, contains a flaw in how it validates web addresses during login and session transfers. An attacker can create a malicious link that appears to belong to a trusted Probo domain but actually redirects the user to a fraudulent website. This can be used in phishing attacks to steal user credentials or distribute malware by exploiting the user's trust in the original domain.

Technologies: [Probo](https://junglewise.ai/threats/technologies/probo). Vendors: [Go](https://junglewise.ai/threats/vendors/go), [Probo](https://junglewise.ai/threats/vendors/probo).

## Quick answers

**Is CVE-2026-49820 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-49820 being exploited in the wild.

**How severe is CVE-2026-49820?** Medium severity, with a CVSS score of 4.7, published 13 August 2026.

**Which products and versions are affected?** go.probo.inc/probo (Go) < 0.204.0, SEMVER:introduced=0,fixed=0.204.0; Probo < 0.204.0.

**Is there a fix for CVE-2026-49820?** Yes. go.probo.inc/probo (Go): upgrade to 0.204.0 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-49820 attacked?** It is attacked over the network, in a software library.

**Am I affected by CVE-2026-49820?** Check whether you run go.probo.inc/probo (Go) or Probo 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

- go.probo.inc/probo (Go): upgrade to 0.204.0 or later

  ```sh
  go get go.probo.inc/probo@v0.204.0
  ```


## Technical details

An open redirect vulnerability exists in Probo's `saferedirect` package due to improper validation of relative paths. The validator incorrectly only inspected the second character of a path; consequently, a payload like `/../\evil.com` would pass validation. When processed by Go's `http.Redirect`, the path is normalized to `/\evil.com`, which many browsers interpret as a host separator, leading to an external redirect. This bypasses same-origin restrictions in OIDC, SAML, and OAuth flows. The issue is fixed in version 0.204.0 (and probod v0.194.1) by implementing `path.Clean` normalization and explicitly rejecting backslashes before validation.

## Affected products

- Probo probo < 0.204.0

## Identifiers

- CVE-2026-49820
- GHSA-x7qq-m748-8p2c
- GO-2026-5861

## Timeline

- 2026-05-26: disclosed
- 2026-06-30: advisory

## References

- [https://api.github.com/users/Fushuling](https://api.github.com/users/Fushuling)
- [https://github.com/Fushuling](https://github.com/Fushuling)
- [https://api.github.com/users/Fushuling/gists%7B/gist_id%7D](https://api.github.com/users/Fushuling/gists%7B/gist_id%7D)
- [https://api.github.com/users/Fushuling/repos](https://api.github.com/users/Fushuling/repos)
- [https://avatars.githubusercontent.com/u/98574309?v=4](https://avatars.githubusercontent.com/u/98574309?v=4)
- [https://api.github.com/users/Fushuling/events%7B/privacy%7D](https://api.github.com/users/Fushuling/events%7B/privacy%7D)

## Related threats

- [Probo privilege escalation to OWNER via createUser](https://junglewise.ai/threats/cve-2026-76079-probo-is-a-self-hostable-governance-risk-and-compliance-grc)
- [Probo GraphQL denial of service via alias flooding](https://junglewise.ai/threats/cve-2026-64861-probo-is-a-self-hostable-governance-risk-and-compliance-grc)
- [Probo console cross-tenant insecure direct object reference in GraphQL](https://junglewise.ai/threats/cve-2026-63505-probo-is-a-self-hostable-governance-risk-and-compliance-grc)