CVE-2024-25622: H2O ignores headers configuration directives
h2o is an HTTP server with support for HTTP/1.x, HTTP/2 and HTTP/3. The configuration directives provided by the headers handler allows users to modify the response headers being sent by h2o. The configuration file of h2o has scopes, and the inner scopes (e.g., path level) are expected to inherit the configuration defined in outer scopes (e.g., global level). However, if a header directive is used in the inner scope, all the definition in outer scopes are ignored. This can lead to headers not being modified as expected. Depending on the headers being added or removed unexpectedly, this behavior could lead to unexpected client behavior. This vulnerability is fixed in commit 123f5e2b65dcdba8f7ef659a00d24bd1249141be.
Affected Software
Remediation
Event History
Frequently Asked Questions
What is the severity of CVE-2024-25622?
CVE-2024-25622 is classified as a moderate severity vulnerability affecting the h2o HTTP server.
How do I fix CVE-2024-25622?
To fix CVE-2024-25622, update your h2o server to a version later than 2024-02-11.
What impact does CVE-2024-25622 have on the h2o server?
CVE-2024-25622 allows unauthorized modification of response headers, potentially affecting security and data integrity.
What versions of h2o are affected by CVE-2024-25622?
CVE-2024-25622 affects all versions of h2o up to and including 2024-02-11.
Is there a workaround for CVE-2024-25622?
Currently, the best workaround for CVE-2024-25622 is to upgrade to a fixed version of h2o.