CVE-2024-25622

Description

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.

CVSS v3.1 Score

3.1

LOW

CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:L/I:N/A:N

Weakness Type (CWE)

CWE-670 CWE-670

Affected Products

Vendor	Product	Versions
dena	h2o	< 2024-02-11

References

Advisories & Patches

https://github.com/h2o/h2o/commit/123f5e2b65dcdba8f7ef659a00d24bd1249141be https://github.com/h2o/h2o/security/advisories/GHSA-5m7v-cj65-h6pj

Exploits

https://github.com/h2o/h2o/security/advisories/GHSA-5m7v-cj65-h6pj

Other References

https://github.com/h2o/h2o/issues/3332

Frequently Asked Questions

What is CVE-2024-25622? +

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. It has a CVSS v3.1 base score of 3.1 (LOW).

How severe is CVE-2024-25622? +

CVE-2024-25622 has a CVSS v3.1 score of 3.1 out of 10, rated LOW. This is a low-severity vulnerability with limited impact.

What products are affected by CVE-2024-25622? +

CVE-2024-25622 affects products from dena, specifically: h2o. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2024-25622? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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