Predictive Vulnerability Intelligence.

Product

  • Product
  • Pricing
  • Documentation

Company

  • About
  • Partnerships
  • Blog
  • Support

Legal

  • Terms
  • Privacy
  • Data Licensing

© 2026 FAUCET Technologies LLC. All rights reserved.

CVE-2023-27522

25
FAUCET Score

CVE-2023-27522 is an HTTP Response Smuggling vulnerability affecting Apache HTTP Server versions 2.4.30 through 2.4.55 when using mod_proxy_uwsgi. This flaw allows special characters in origin response headers to truncate or split responses forwarded to clients. Rated 7.5 HIGH, it has a network attack vector, low attack complexity, and can lead to high integrity impact without requiring user interaction. Currently, there is no evidence of active exploitation, public exploit code, or significant community discussion, and it is not listed in CISA's KEV catalog.

Impacted Technologies

VendorProductVersion(s)CPE
>= 2.4.30, < 2.4.56CPE matchmatch criteria
cpe:2.3:a:apache:http_server:*:*:*:*:*:*:*:*
10.0CPE matchmatch criteria
cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:*
< 2.0.22CPE matchmatch criteria
cpe:2.3:a:unbit:uwsgi:*:*:*:*:*:*:*:*
>= 2.4.30, <= 2.4.55CPE match
cpe:2.3:a:apache:http_server:*:*:*:*:*:*:*:*

CVSS Data

CVSS version used by this source: 3.1

7.5HIGH

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

Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality Impact
NONE
Integrity Impact
HIGH
Availability Impact
NONE
Exploitability Score
3.9
Impact Score
3.6
CvssVersion
3.1

Exploit Intelligence

EPSS Score
2.13%
Probability of exploitation in next 30 days
EPSS Percentile
80.1%
Percentile rank of EPSS score among Peer Group
As of 2026-07-27
Model: v2026.06.15
This CVE's current EPSS score of 0.0213 is in the 65th percentile among its peer group of 51,551 CVEs.

Social Chatter

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

Media Mentions

The average CVE in this peer group has 0.1 InfoSec Media, 0.0 Vendor Blog, and 0.0 Security Researcher mentions.

Remediation

Patch Available

Vendor Patches (11)

apachepatch availablevia llm_extracted
Fixed in: 2.4
microsoftpatch availablevia msrc
Product: cm1 httpd 2.4.56-1 on CBL Mariner 1.0Fixed in: 2.4.56-1
microsoftpatch availablevia msrc
Product: cbl2 httpd 2.4.56-1 on CBL Mariner 2.0Fixed in: 2.4.56-1
pippatch availablevia ghsa
Product: uWSGIFixed in: 2.0.22
redhatpatch availablevia redhat_api
Product: Red Hat Enterprise Linux 8Fixed in: httpd:2.4-8080020230830144124.63b34585
View patch
redhatpatch availablevia redhat_api
Product: Red Hat Enterprise Linux 8.6 Extended Update SupportFixed in: httpd:2.4-8060020230830144749.ad008a3a
View patch
redhatpatch availablevia redhat_api
Product: Red Hat Enterprise Linux 9Fixed in: httpd-0:2.4.57-5.el9
View patch
redhatpatch availablevia redhat_api
Product: Red Hat Enterprise Linux 9.2 Extended Update SupportFixed in: httpd-0:2.4.53-11.el9_2.6
View patch
redhatpatch availablevia redhat_api
Product: Text-Only JBCSFixed in: httpd
View patch
redhatpatch availablevia redhat_api
Product: JBoss Core Services on RHEL 7Fixed in: jbcs-httpd24-httpd-0:2.4.57-5.el7jbcs
View patch
redhatpatch availablevia redhat_api
Product: JBoss Core Services for RHEL 8Fixed in: jbcs-httpd24-httpd-0:2.4.57-5.el8jbcs
View patch

Vendor Advisories (6)

apachellm-apache-f398f8ed28802aa3LOW

Apache HTTP Server 2.4 vulnerabilities - The Apache HTTP Server Project

Mar 2, 2026
apachellm-apache-a7a91ec4c0e9421dHIGH

Apache HTTP Server 2.4 vulnerabilities - The Apache HTTP Server Project

Dec 10, 2025
microsoft2023-Mar/CVE-2023-27522Important

Apache HTTP Server: mod_proxy_uwsgi HTTP response splitting

Mar 14, 2023
pipGHSA-vcph-37mh-fqrhhigh

Apache HTTP Server via mod_proxy_uwsgi HTTP response smuggling

Mar 7, 2023
redhatCVE-2023-27522Moderate

httpd: mod_proxy_uwsgi HTTP response splitting

Mar 7, 2023
apachellm-apache-684e4d0003611bd4LOW

Apache HTTP Server 2.4 vulnerabilities - The Apache HTTP Server Project

References

httpd.apache.org / security/vulnerabilities_24.html
Vendor Advisory
lists.debian.org / debian-lts-announce/2023/04/msg00028.html
Third Party Advisory
security.gentoo.org / glsa/202309-01
Third Party Advisory