CVE-2026-75833 (GCVE-0-2026-75833)

Vulnerability from cvelistv5 – Published: 2026-08-18 11:19 – Updated: 2026-08-18 13:42
VLAI
Title
Grav API Plugin Open Redirect via Backslash Bypass
Summary
The Grav API plugin (getgrav/grav-plugin-api, bundled with Grav 2.0's admin-next/API stack) before version 1.0.14 contains an open redirect weakness in SsoController::sanitizeReturnTo(). The function rejects a literal '//' prefix but does not account for browsers normalizing backslashes to slashes in special (http/https) schemes, so a returnTo value such as '/\evil.com' passes the guard and is later resolved by the browser as the protocol-relative URL '//evil.com'. Following a legitimate OAuth login flow, an attacker-supplied returnTo parameter could redirect an authenticated victim to an attacker-controlled site for post-login phishing. Full browser-side exploitability depends on the admin-next SPA's client-side oauth-callback handler and was not independently verified by the reporter.
Severity
8.6 (High)
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
4.2 (Medium)
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:L/I:L/A:N
SSVC
Exploitation: poc Automatable: no Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-08-18 13:41 UTC
CWE
  • CWE-601 - URL Redirection to Untrusted Site ('Open Redirect')
Assigner
VulnCheck CNA under the mitre root
CNA scorecard B 84/100 over 6903 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
getgrav grav Affected: 0 , < 1.0.14 (semver)
Unaffected: 1.0.14 (semver)
    cpe:2.3:a:getgrav:grav:*:*:*:*:*:*:*:*
Create a notification for this product.
Date Public
2026-08-03 00:00
Credits
iaohkut-from-NightWolf-Team
Show details on NVD website
To clipboard 

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