There is no restriction on the amount of attachment headers that a message can contain when being deserialized by Apache CXF, which can lead to uncontrolled resource consumption or a denial of service attack. Users are recommended to upgrade to versions 4.2.2 or 4.1.7 or 3.6.12, which fix this issue by imposing a maximum default of 500 attachments per message.

All versions of Apache Santuario - XML Security for Java prior to 2.2.3 and 2.1.7 are vulnerable to an issue where the "secureValidation" property is not passed correctly when creating a KeyInfo from a KeyInfoReference element. This allows an attacker to abuse an XPath Transform to extract any local .xml files in a RetrievalMethod element.

A further incomplete fix for a previous advisory CVE-2026-44417 (Untrusted JMS configuration can lead to RCE) for Apache CXF has been identified, which can allow code execution capabilities, if untrusted users are allowed to configure JMS for Apache CXF. Users are recommended to upgrade to versions 4.2.2 or 4.1.7 or 3.6.12, which fixes this issue.

A race condition in AbstractOAuthDataProvider allows concurrent requests using the same Refresh Token to bypass single-use semantics and generate multiple valid Access Tokens, when 'recycleRefreshTokens' is set to false. A leaked refresh token can be replayed concurrently by multiple attackers or threads. Users are recommended to upgrade to versions 4.2.2 or 4.1.7 or 3.6.12, which fixes this issue.

A JNDI Injection vulnerability has been discovered in Apache CXF's JCA integration module, which can allow for code execution, if an attacker is able to manipulate the JCA deployment descriptor (ra.xml) or runtime activation parameters. Users are recommended to upgrade to versions 4.2.2 or 4.1.7 or 3.6.12, which fixes this issue.

The OpenID Connect Core 1.0 specification mandates that the RP MUST validate the chash 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 chash, 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.

In Apache CXF's DefaultEncryptingOAuthDataProvider, revoked access tokens still decrypt successfully, and TokenIntrospectionService reports active:true. The same applies to refresh tokens. This violates the RFC stipulations that 'The authorization server MUST invalidate the token.' and 'introspection of a revoked token MUST return {"active":false}'. Users are recommended to upgrade to versions 4.2.3 or 4.1.8 or 3.6.12, which fix this issue.

Apache CXF reads a top-level WSDL through its hardened StaxUtils path, which disables XML DTDs and external entities. However, any <wsdl:import> or <xsd:import> referenced from that top-level WSDL is handed off to WSDL4J, which does not disable DOCTYPE declarations or external entities. As a result, the protections applied to the top-level document do not extend to imported documents, leaving imported WSDL/XSD content vulnerable to XML External Entity (XXE) attacks. Users are recommended to upgrade to versions 4.2.3 or 4.1.8 or 3.6.12, which fix this issue.

Apache CXF allows to set a limit on the number of form parameters in a JAX-RS message via the "maxFormParameterCount" configuration option. However, no default limit is set which may lead to denial of service attacks when processing  requests with very large numbers of form parameters. Users are recommended to upgrade to versions 4.2.3 or 4.1.8 or 3.6.12, which fix this issue by using a default limit of 500 parameters.

A race condition in JCacheCodeDataProvider allows an attacker to redeem a single authorization code multiple times via concurrent requests, resulting in the issuance of multiple distinct, valid access tokens. Users are recommended to upgrade to versions 4.2.3, 4.1.8 or 3.6.12, which fix this issue.

Apache CXF allows to control the maximum attachment size via the "attachment-max-size". Prior to Apache CXF 4.2.3 and 4.1.8 and 3.6.12, there was no default placed on this size, meaning that a denial of service attack is possible if the user doesn't explicitly set the limit. Users should update to Apache CXF 4.2.3 or 4.1.8 or 3.6.12 which fixes this problem by imposing a default attachment size limit of 50mb.

An incomplete fix for CVE-2026-50645 means that it is still possible to perform a denial of service attack on Apache CXF by sending a message with many attachment headers. Users are recommended to upgrade to versions 4.2.3 or 4.1.8 or 3.6.12, which fix this issue.

A SSRF vulnerability in WADL service description in versions of Apache CXF before 4.0.5, 3.6.4 and 3.5.9 allows an attacker to perform SSRF style attacks on REST webservices. The attack only applies if a custom stylesheet parameter is configured.

Apache CXF could allow a remote attacker to obtain sensitive information, caused by a flaw when ships with OpenId Connect JWK Keys service. By accessing the JWK keystore file, an attacker could exploit this vulnerability to obtain the public keys in JWK format, and use this information to launch further attacks against the affected system.

A flaw was found in the way Apache CXF handle exceptions when CXF is configured to use the com.sun.net.ssl implementation via System.setProperty("java.protocol.handler.pkgs", "com.sun.net.ssl.internal.www.protocol") function. When this system property is set, CXF uses some reflection to try to make the HostnameVerifier work with the old com.sun.net.ssl.HostnameVerifier interface. However, the default HostnameVerifier implementation in CXF does not implement the method in this interface therefore an exception is thrown. The exception is caught in the reflection code but not properly propagated which leaves CXF client subject to man-in-the-middle attacks.

Upstream Patch: https://github.com/apache/cxf/commit/fae6fabf9bd7647f5e9cb68897a7d7

A potential denial of service vulnerability is present in versions of Apache CXF before 3.5.10, 3.6.5 and 4.0.6. In some edge cases, the CachedOutputStream instances may not be closed and, if backed by temporary files, may fill up the file system (it applies to servers and clients).

In versions of Apache CXF before 3.6.4 and 4.0.5 (3.5.x and lower versions are not impacted), a CXF HTTP client conduit may prevent HTTPClient instances from being garbage collected and it is possible that memory consumption will continue to increase, eventually causing the application to run out of memory

An improper input validation of the p2c parameter in the Apache CXF JOSE code before 4.0.5, 3.6.4 and 3.5.9 allows an attacker to perform a denial of service attack by specifying a large value for this parameter in a token.

A vulnerability in Apache CXF before versions 3.5.5 and 3.4.10 allows an attacker to perform a remote directory listing or code exfiltration. The vulnerability only applies when the CXFServlet is configured with both the static-resources-list and redirect-query-check attributes. These attributes are not supposed to be used together, and so the vulnerability can only arise if the CXF service is misconfigured.

A vulnerability in the JsonMapObjectReaderWriter of Apache CXF allows an attacker to submit malformed JSON to a web service, which results in the thread getting stuck in an infinite loop, consuming CPU indefinitely. This issue affects Apache CXF versions prior to 3.4.4; Apache CXF versions prior to 3.3.11.

Apache CXF is vulnerable to a denial of service, caused by improper validation of requesturi parameter by the OAuth 2 authorization service. By sending a specially-crafted request, a remote attacker could exploit this vulnerability to cause a denial of service condition on the authorization server.

An Apache CXF endpoint can be used as an intermediary, where a token credential from the received message is used as a delegation token to obtain a new token from a Security Token Service (STS) for the outbound request.

By default, the token retrieved from the STS is cached and associated with the delegation token via an identifier extracted from the delegation token.

However, there is a weakness in how the identifier is extracted from the delegation token, which means that an attacker could craft a token which would return an identifer corresponding to a cached token for another user.

External References:

http://cxf.apache.org/security-advisories.data/CVE-2017-5656.txt.asc

Upstream patch:

https://github.com/apache/cxf/commit/66c2c5b99e01a2165a2c5ed9ae34b4b9a512cb39

Apache CXF JAX-RS implementation provides a number of Atom MessageBodyReaders. These readers use Apache Abdera Parser to parse Atom feeds or Entries, with this Parser expanding XML entities by default. This represents a major XXE risk.

External References:

http://cxf.apache.org/security-advisories.data/CVE-2016-8739.txt.asc?version=1&modificationDate=1482164360575&api=v2

Apache CXF OAuth2 Hawk and JOSE MAC Validation code is not using a constant time MAC signature comparison algorithm which may be exploited by some sophisticated timing attacks. It may only affect OAuth2 Hawk or JWT access tokens or JOSE JWS/JWE interceptors which depend on HMac secret key algorithms.

This vulnerability affects all versions of Apache CXF prior to 3.0.13, 3.1.10.

Upstream patches:

CXF 3.1.x: http://git-wip-us.apache.org/repos/asf/cxf/commit/555843f9

CXF 3.0.x http://git-wip-us.apache.org/repos/asf/cxf/commit/1338469f

CXF 3.2.0-SNAPSHOT (master): http://git-wip-us.apache.org/repos/asf/cxf/commit/e66ce235

External References:

https://cxf.apache.org/security-advisories.data/CVE-2017-3156.txt.asc

The fix for CVE-2025-48913: Apache CXF: Untrusted JMS configuration can lead to RCE was not complete, meaning that another path in the code might lead to code execution capabilities, if untrusted users are allowed to configure JMS for Apache CXF. Users are recommended to upgrade to versions 4.2.1, 4.1.6 or 3.6.11, which fix this issue.

The JwtAccessTokenValidator class in Apache CXF fails to validate the 'aud' (Audience) claims of incoming JWT access tokens. This allows a JWT issued for one Resource Server to be successfully replayed against a completely different Resource Server, leading to Token Confusion/Routing attacks. Users are recommended to upgrade to versions 4.2.2 or 4.1.7, which fixes this issue.

If untrusted users are allowed to configure JMS for Apache CXF, previously they could use RMI or LDAP URLs, potentially leading to code execution capabilities. This interface is now restricted to reject those protocols, removing this possibility.

Users are recommended to upgrade to versions 3.6.8, 4.0.9 or 4.1.3, which fix this issue.

Tibor Jager, Kenneth G. Paterson and Juraj Somorovsky have described XML encryption backwards compatibility attacks against various frameworks, including Apache CXF. An attacker can use these flaws to force a server to utilize insecure, legacy cryptosystems when secure cryptosystems are enabled on endpoints. This could expose flaws in the underlying legacy cryptosystems, such as CVE-2011-1096 and CVE-2011-2487. This flaw also affects the jbossws-native stack.