CVE-2021-20718
CVE-2021-20718 is a high-severity vulnerability in Openidc Mod Auth Openidc with a CVSS 3.x base score of 7.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-400.
Key facts
- Severity: High (CVSS 3.x base score 7.5)
- CVSS v2: 5.0
- EPSS exploit prediction: 3% (87th percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-400
- Affected product: Openidc Mod Auth Openidc
- Published:
- Last modified:
Description
mod_auth_openidc 2.4.0 to 2.4.7 allows a remote attacker to cause a denial-of-service (DoS) condition via unspecified vectors.
Frequently asked questions
- What is CVE-2021-20718?
- mod_auth_openidc 2.4.0 to 2.4.7 allows a remote attacker to cause a denial-of-service (DoS) condition via unspecified vectors.
- How severe is CVE-2021-20718?
- CVE-2021-20718 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
- Is CVE-2021-20718 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (87th percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2021-20718?
- CVE-2021-20718 primarily affects Openidc Mod Auth Openidc. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
- How do I fix CVE-2021-20718?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
- When was CVE-2021-20718 published?
- CVE-2021-20718 was published on 2021-05-20 and last updated on 2026-06-17.
References
- https://github.com/zmartzone/mod_auth_openidc
- https://jvn.jp/en/jp/JVN49704918/index.html
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/5HJK366TLFEOIYWTHQSZO24MSDPBXHJU/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/FV4KYMQWPS3I2QPW2C253MLIAFGBZPLK/
- https://www.oracle.com/security-alerts/cpujan2022.html
- https://www.zmartzone.eu/
Affected products (4)
- cpe:2.3:a:openidc:mod_auth_openidc:*:*:*:*:*:*:*:*
- cpe:2.3:o:fedoraproject:fedora:33:*:*:*:*:*:*:*
- cpe:2.3:o:fedoraproject:fedora:34:*:*:*:*:*:*:*
- cpe:2.3:a:oracle:essbase:*:*:*:*:*:*:*:*
More vulnerabilities in Openidc Mod Auth Openidc
- CVE-2017-6413 — High (CVSS 8.6): The "OpenID Connect Relying Party and OAuth 2.0 Resource Server" (aka mod_auth_openidc) module before 2.1.6 for the…
- CVE-2017-6062 — High (CVSS 8.6): The "OpenID Connect Relying Party and OAuth 2.0 Resource Server" (aka mod_auth_openidc) module before 2.1.5 for the…
- CVE-2024-24814 — High (CVSS 7.5): mod_auth_openidc is an OpenID Certified™ authentication and authorization module for the Apache 2.x HTTP server that…
- CVE-2023-28625 — High (CVSS 7.5): mod_auth_openidc is an authentication and authorization module for the Apache 2.x HTTP server that implements the…
- CVE-2017-6059 — High (CVSS 7.5): Mod_auth_openidc.c in the Ping Identity OpenID Connect authentication module for Apache (aka mod_auth_openidc) before…
- CVE-2019-20479 — Medium (CVSS 6.1): A flaw was found in mod_auth_openidc before version 2.4.1. An open redirect issue exists in URLs with a slash and…
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