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.

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

Q: 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.

Q: How is CVE-2026-49820 attacked?

It is attacked over the network, in a software library.

Q: 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.

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. Vendors: Go, 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
```
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

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