How severe is CVE-2026-57817?

CVE-2026-57817 has a CVSS 3.x base score of 8.1, rated high severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2026-57817 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (37th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-57817?

CVE-2026-57817 affects Apache Cxf. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-57817?

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-2026-57817 published?

CVE-2026-57817 was published on 2026-08-06 and last updated on 2026-08-07.

CVE-2026-57817

CVE-2026-57817 is a high-severity vulnerability in Apache Cxf with a CVSS 3.x base score of 8.1. 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-20.

Key facts

Severity: High (CVSS 3.x base score 8.1)
EPSS exploit prediction: 0% (37th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Apache Cxf
Published: 2026-08-06
Last modified: 2026-08-07

Description

The OpenID Connect Core 1.0 specification mandates that the RP MUST validate the `c_hash` parameter when operating in the Hybrid Flow. If an Apache CXF RP is integrated with a non-compliant or misconfigured Identity Provider (IdP) that omits the `c_hash`, the RP becomes vulnerable to Authorization Code Substitution/Injection attacks. Users are recommended to upgrade to versions 4.2.3 or 4.1.8 or 3.6.12, which fix this issue.

Frequently asked questions

What is CVE-2026-57817?: The OpenID Connect Core 1.0 specification mandates that the RP MUST validate the `c_hash` parameter when operating in the Hybrid Flow. If an Apache CXF RP is integrated with a non-compliant or misconfigured Identity Provider (IdP) that omits the `c_hash`, the RP becomes vulnerable to Authorization Code Substitution/Injection attacks. Users are recommended to upgrade to versions 4.2.3 or 4.1.8 or 3.6.12, which fix this issue.
How severe is CVE-2026-57817?: CVE-2026-57817 has a CVSS 3.x base score of 8.1, rated high severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2026-57817 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (37th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-57817?: CVE-2026-57817 affects Apache Cxf. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-57817?: 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-2026-57817 published?: CVE-2026-57817 was published on 2026-08-06 and last updated on 2026-08-07.

References

Affected products (1)

cpe:2.3:a:apache:cxf:*:*:*:*:*:*:*:*

More vulnerabilities in Apache Cxf

CVE-2012-2379 — Critical (CVSS 10.0): Apache CXF 2.4.x before 2.4.8, 2.5.x before 2.5.4, and 2.6.x before 2.6.1, when a Supporting Token specifies a child…
CVE-2026-68079 — Critical (CVSS 9.8): In Apache CXF's DefaultEncryptingCodeDataProvider, a captured authorization code can be redeemed an unlimited number…
CVE-2026-66909 — Critical (CVSS 9.8): Apache CXF's JMS transport deserializes the body of any inbound JMS ObjectMessage using native Java deserialization,…
CVE-2026-50628 — Critical (CVSS 9.8): A logic error in OAuthRequestFilter rejects legitimate requests originating from the bound IP address, while blindly…
CVE-2026-49875 — Critical (CVSS 9.8): Apache CXF's EndpointReferenceUtils and W3CMultiSchemaFactory classes construct a SAXParserFactory without the…
CVE-2026-44930 — Critical (CVSS 9.8): An LDAP injection vulnerability in the LDAP Certificate repository of the XKMS server in Apache CXF may allow an…

All CVEs affecting Apache Cxf →

Other CWE-20 (Improper Input Validation) vulnerabilities

CVE-2026-48056 — Critical (CVSS 10.0): Streambert is a cross-platform Electron Desktop App to stream and download video content. Versions prior to 2.5.0…
CVE-2026-33267 — Critical (CVSS 10.0): Improper Input Validation vulnerability in Apache Traffic Server. This issue affects Apache Traffic Server: from 9.2.0…
CVE-2026-47668 — Critical (CVSS 10.0): DbGate is cross-platform database manager. In versions 7.1.8 and prior, DbGate's JSON script runner (`POST…
CVE-2026-16117 — Critical (CVSS 10.0): Impact: @fastify/http-proxy versions up to and including 11.5.0 fail to rewrite the request prefix when the prefix…
CVE-2026-48316 — Critical (CVSS 10.0): ColdFusion versions 2025.9, 2023.20 and earlier are affected by an Improper Input Validation vulnerability that could…
CVE-2026-48281 — Critical (CVSS 10.0): ColdFusion versions 2025.9, 2023.20 and earlier are affected by an Improper Input Validation vulnerability that could…

Browse all CWE-20 (Improper Input Validation) vulnerabilities →