CVE-2026-63718 Apache HTTP Server: mod_proxy_uwsgi Transfer-Encoding response smuggling

What is CVE-2026-63718?

CVE-2026-63718 is a high-severity vulnerability in Apache Http Server, published on 1 Oct 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official description

Inconsistent Interpretation of HTTP Requests ('HTTP Request/Response Smuggling') response smuggling vulnerability in Apache HTTP Server via mod_proxy_uwsgi and a crafted uwsgi response with Transfer-Encoding.

This issue affects Apache HTTP Server: from 2.4.30 through 2.4.68.

Weakness: CWE-444

Which versions are affected by CVE-2026-63718?

1 open source package ship an affected version, including apache. It affects 1 product.

Products include Apache Http Server.

How do I fix CVE-2026-63718?

Upgrade apache to 2.4.69 or later.

Is CVE-2026-63718 being exploited?

There is no known exploitation of CVE-2026-63718 in the wild and no public exploit code.

Other vulnerabilities in Apache Http Server

• CVE-2021-42013 Apache HTTP Server Path Traversal Exploited Critical 9.8
• CVE-2024-38475 Apache HTTP Server Improper Escaping of Output Exploited Critical 9.1
• CVE-2021-40438 Apache HTTP Server-Side Request Forgery (SSRF) Exploited Critical 9.0
• CVE-2019-0211 Apache HTTP Server Privilege Escalation Exploited High 7.8
• CVE-2021-41773 Apache HTTP Server Path Traversal Exploited High 7.5

All Apache Http Server vulnerabilities

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as ALPINE-CVE-2026-63718, AZL-108080, BELL-CVE-2026-63718, BIT-apache-2026-63718, DEBIAN-CVE-2026-63718, ECHO-3b80-2eed-e08d and 4 more.