CVE-2026-33523

FAUCET Score

HTTP response splitting vulnerability in multiple Apache HTTP Server modules with untrusted or compromised backend servers. This issue affects Apache HTTP Server: from through 2.4.66. Users are recommended to upgrade to version 2.4.67, which fixes the issue.

First published: May 4, 2026Last modified: May 4, 2026

Impacted Technologies

Vendor	Product	Version(s)	CPE
		>= 2.4.0, <= 2.4.66CPE match	cpe:2.3:a:apache:http_server::::::::
		>= 2.4.0, < 2.4.67CPE matchmatch criteria	cpe:2.3:a:apache:http_server::::::::

CVSS Data

CVSS version used by this source: 3.1

6.5MEDIUM

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

Attack Vector

NETWORK

Attack Complexity

LOW

Privileges Required

NONE

User Interaction

NONE

Scope

UNCHANGED

Confidentiality Impact

LOW

Integrity Impact

LOW

Availability Impact

NONE

Exploitability Score

3.9

Impact Score

2.5

CvssVersion

3.1

Exploit Intelligence

EPSS Score

0.44%

Probability of exploitation in next 30 days

EPSS Percentile

35.7%

Percentile rank of EPSS score among Peer Group

As of 2026-07-27

Model: v2026.06.15

This CVE's current EPSS score of 0.0044 is in the 22nd percentile among its peer group of 23,723 CVEs.

Social Chatter

The average CVE in this peer group has 0.0 Twitter, 0.0 Reddit, 0.1 Bluesky, 0.0 Mastodon, and 0.4 GitHub mentions.

Media Mentions

The average CVE in this peer group has 0.0 InfoSec Media, 0.0 Vendor Blog, and 0.0 Security Researcher mentions.

Remediation

Patch Available

Vendor Patches (12)

apachepatch availablevia llm_extracted

Fixed in: 2.4

microsoftpatch availablevia msrc

Product: 21220-17084Fixed in: 2.4.67-1

microsoftpatch availablevia msrc

Product: azl3 httpd 2.4.66-1 on Azure Linux 3.0Fixed in: 2.4.67-1