USN-7639-1: Apache HTTP Server vulnerabilities

USN-7639-1: Apache HTTP Server vulnerabilities

Publication date: 16 July 2025
Overview: Several security issues were fixed in Apache HTTP Server.

Packages
apache2 - Apache HTTP server

Details
It was discovered that the Apache HTTP Server incorrectly handled certain
Content-Type response headers. A remote attacker could possibly use this
issue to perform HTTP response splitting attacks. (CVE-2024-42516)

xiaojunjie discovered that the Apache HTTP Server mod_proxy module
incorrectly handled certain requests. A remote attacker could possibly use
this issue to send outbound proxy requests to an arbitrary URL.
(CVE-2024-43204)

John Runyon discovered that the Apache HTTP Server mod_ssl module
incorrectly escaped certain data. A remote attacker could possibly use this
issue to insert escape characters into log files. (CVE-2024-47252)

Sven Hebrok, Felix Cramer, Tim Storm, Maximilian Radoy, and Juraj
Somorovsky discovered that the Apache HTTP Server mod_ssl module
incorrectly handled TLS 1.3 session resumption. A remote attacker could
possibly use this issue to bypass access control. (CVE-2025-23048)

Anthony CORSIEZ discovered that the Apache HTTP Server mod_proxy_http2
module incorrectly handled missing host headers. A remote attacker could
possibly use this issue to cause the server to crash, resulting in a denial
of service. (CVE-2025-49630)

Robert Merget discovered that the Apache HTTP Server mod_ssl module
incorrectly handled TLS upgrades. A remote attacker could possibly use this
issue to hijack an HTTP session. This update removes the old “SSLEngine
optional” configuration option, possibly requiring a configuration change
in certain environments. (CVE-2025-49812)

Gal Bar Nahum discovered that the Apache HTTP Server incorrectly handled
certain memory operations. A remote attacker could possibly use this
issue to cause the server to consume resources, leading to a denial of
service. (CVE-2025-53020)

Update instructions
The problem can be corrected by updating your system to the following package versions:

• 25.04 plucky: apache2 – 2.4.63-1ubuntu1.1
• 24.04 noble: apache2 – 2.4.58-1ubuntu8.7
• 22.04 jammy: apache2 – 2.4.52-1ubuntu4.15