CVE-2021-29456
MEDIUMDescription
Authelia is an open-source authentication and authorization server providing 2-factor authentication and single sign-on (SSO) for your applications via a web portal. In versions 4.27.4 and earlier, utilizing a HTTP query parameter an attacker is able to redirect users from the web application to any domain, including potentially malicious sites. This security issue does not directly impact the security of the web application itself. As a workaround, one can use a reverse proxy to strip the query parameter from the affected endpoint. There is a patch for version 4.28.0.
How to fix
Remediation is compiled from vendor and distribution security advisories. Always confirm against the linked source for your exact version and platform.
CVSS v3 Vector
Exploitability
Impact
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:H/A:N
Exploit Intelligence
Low risk: more likely to be exploited than 40% of all known CVEs.
References
Related Vulnerabilities
Other CWE-601 (Open Redirect) vulnerabilities, ordered by exploit likelihood. View all
| CVE | Severity | CVSS | EPSS | Exploited | Fix |
|---|---|---|---|---|---|
| CVE-2025-4123 | High | 7.6 | 98% | - | Fix |
| CVE-2018-11784 | Medium | 4.3 | 94% | - | Fix |
| CVE-2021-22881 | Medium | 6.1 | 87% | - | Fix |
| CVE-2022-45402 | Medium | 6.1 | 82% | - | Fix |
| CVE-2017-1000117 | High | 8.8 | 78% | - | Fix |
| CVE-2019-10098 | Medium | 6.1 | 74% | - | Fix |
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Markdown
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Start freeThis product uses NVD data but is not endorsed or certified by the NVD. EPSS scores courtesy of FIRST.org (https://www.first.org/epss). Source: CISA KEV Catalog. Data as of 2024-11-21.