CVE-2026-63686

Summary

A NULL pointer dereference vulnerability in Apache HTTP Server's mod_xml2enc module allows untrusted backend servers to trigger a denial of service condition when processing proxied responses with problematic charset conversions. This can lead to server crashes and unavailability.

Exploitability

Exploitation requires an untrusted backend server to send a specially crafted proxied response with a charset conversion that partially succeeds then fails, making it moderately difficult to achieve in practice but possible with a compromised or malicious backend.

Blast radius

The impact is significant as the vulnerability affects all platforms and allows for complete denial of service, potentially causing widespread availability issues for web applications relying on Apache HTTP Server's proxy functionality.

Detection

No reliable host or network indicator is derivable from the published description.

Prioritized remediation

Upgrade to Apache HTTP Server 2.4.69 which fixes this NULL pointer dereference issue in mod_xml2enc.

Analysis generated locally by garnet-coder (no data left the box). AI-assisted — verify against primary sources before acting.