CVE-2026-49820

Probo has an open redirect bypass via path normalization

Published Aug 13, 2026 CVSS 3.1 · 4.7 Medium EPSS < 1% KEV · Not listed
Description
Probo is a self-hostable governance, risk, and compliance (GRC) platform built for engineering and security teams. Probo's `saferedirect` package validates redirect URLs used across authentication flows (OIDC, SAML, session transfer, OAuth connectors, and trust-center magic links). Prior to version 0.19.3.1, the validator only inspected the second character of relative paths, so a URL like `/../\evil.com` passed validation because the second character is `.`. Go's `http.Redirect` normalizes this path to `/\evil.com` before setting the `Location` header. Browsers can interpret the backslash as a host separator and redirect the user to an external domain (`https://evil.com`), bypassing the intended same-origin restriction. This enables open-redirect phishing: an attacker can craft a `continue` parameter (or embed a malicious URL in a session-transfer token) that appears to originate from a trusted Probo domain but redirects victims elsewhere. This is fixed in `go.probo.inc/probo` 0.193.1 by normalizing relative paths with `path.Clean` before validation, rejecting backslashes (including percent-encoded `%5c`) anywhere in the path, and re-checking the normalized result for protocol-relative and backslash prefixes. Self-hosted deployments should upgrade to probod v0.194.1 or later. SaaS deployments on getprobo.com are patched. No practical workaround is available for self-hosted installations.

Remediation

No solution or workaround provided in the CVE record

Tracking

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Advisories

Source ID Title
Github GHSA Github GHSA GHSA-x7qq-m748-8p2c Probo has an open redirect bypass via path normalization
History
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Type Values Removed Values Added
First Time appeared Getprobo
Getprobo probo
Vendors & Products Getprobo
Getprobo probo
Type Values Removed Values Added
Description Probo is a self-hostable governance, risk, and compliance (GRC) platform built for engineering and security teams. Probo's `saferedirect` package validates redirect URLs used across authentication flows (OIDC, SAML, session transfer, OAuth connectors, and trust-center magic links). Prior to version 0.19.3.1, the validator only inspected the second character of relative paths, so a URL like `/../\evil.com` passed validation because the second character is `.`. Go's `http.Redirect` normalizes this path to `/\evil.com` before setting the `Location` header. Browsers can interpret the backslash as a host separator and redirect the user to an external domain (`https://evil.com`), bypassing the intended same-origin restriction. This enables open-redirect phishing: an attacker can craft a `continue` parameter (or embed a malicious URL in a session-transfer token) that appears to originate from a trusted Probo domain but redirects victims elsewhere. This is fixed in `go.probo.inc/probo` 0.193.1 by normalizing relative paths with `path.Clean` before validation, rejecting backslashes (including percent-encoded `%5c`) anywhere in the path, and re-checking the normalized result for protocol-relative and backslash prefixes. Self-hosted deployments should upgrade to probod v0.194.1 or later. SaaS deployments on getprobo.com are patched. No practical workaround is available for self-hosted installations.
Title Probo has an open redirect bypass via path normalization
Weaknesses CWE-601
References
Metrics cvssV3_1

{'score': 4.7, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:N/I:L/A:N'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
GitHub_M
Published
Updated
Aug 14, 2026, 3:40 PM
Reserved
Jun 1, 2026, 6:50 PM
Status
Deferred
Published
Aug 13, 2026, 3:19 PM
Modified
Oct 24, 2026, 4:10 PM