Apache HTTP Server up to 2.4.68 mod_proxy_uwsgi expected behavior violation

Summaryinfo

A vulnerability, which was classified as critical, has been found in Apache HTTP Server up to 2.4.68. This issue affects some unknown processing of the component mod_proxy_uwsgi. This manipulation causes expected behavior violation. This vulnerability is registered as CVE-2026-63718. Remote exploitation of the attack is possible. No exploit is available.

Detailsinfo

A vulnerability has been found in Apache HTTP Server up to 2.4.68 and classified as critical. Affected by this vulnerability is an unknown functionality of the component mod_proxy_uwsgi. The manipulation with an unknown input leads to a expected behavior violation vulnerability. The CWE definition for the vulnerability is CWE-440. A feature, API, or function does not perform according to its specification. As an impact it is known to affect confidentiality, integrity, and availability. The summary by CVE is:

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.

It is possible to read the advisory at httpd.apache.org. This vulnerability is known as CVE-2026-63718 since 07/17/2026. The exploitation appears to be easy. The attack can be launched remotely. The exploitation doesn't need any form of authentication. The technical details are unknown and an exploit is not publicly available. The pricing for an exploit might be around USD $5k-$25k at the moment (estimation calculated on 10/01/2026).

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

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Productinfo

Type

• Web Server

Vendor

• Apache

Name

• HTTP Server

Version

• 2.4.0
• 2.4.1
• 2.4.2
• 2.4.3
• 2.4.4
• 2.4.5
• 2.4.6
• 2.4.7
• 2.4.8
• 2.4.9
• 2.4.10
• 2.4.11
• 2.4.12
• 2.4.13
• 2.4.14
• 2.4.15
• 2.4.16
• 2.4.17
• 2.4.18
• 2.4.19
• 2.4.20
• 2.4.21
• 2.4.22
• 2.4.23
• 2.4.24
• 2.4.25
• 2.4.26
• 2.4.27
• 2.4.28
• 2.4.29
• 2.4.30
• 2.4.31
• 2.4.32
• 2.4.33
• 2.4.34
• 2.4.35
• 2.4.36
• 2.4.37
• 2.4.38
• 2.4.39
• 2.4.40
• 2.4.41
• 2.4.42
• 2.4.43
• 2.4.44
• 2.4.45
• 2.4.46
• 2.4.47
• 2.4.48
• 2.4.49
• 2.4.50
• 2.4.51
• 2.4.52
• 2.4.53
• 2.4.54
• 2.4.55
• 2.4.56
• 2.4.57
• 2.4.58
• 2.4.59
• 2.4.60
• 2.4.61
• 2.4.62
• 2.4.63
• 2.4.64
• 2.4.65
• 2.4.66
• 2.4.67
• 2.4.68

License

• open-source

Website

• Vendor: https://www.apache.org/

CPE 2.3info

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CPE 2.2info

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