CVE-2023-40225

Name: CVE-2023-40225
Creator: NVD / NIST
Published: 2023-08-10T21:15:10.743+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

HIGHCVSS 7.2/10EPSS 1.81%

Last modified Jun 17, 2026

CVE-2023-40225 is a high-severity vulnerability rated 7.2/10 on the CVSS scale. HAProxy through 2.0.32, 2.1.x and 2.2.x through 2.2.30, 2.3.x and 2.4.x through 2.4.23, 2.5.x and 2.6.x before 2.6.15, 2.7.x before 2.7.10, and 2.8.x before 2.8.2 forwards empty Content-Length headers, violating RFC 9110 section 8.6. In uncommon cases, an HTTP/1 server behind HAProxy may interpret the payload as an extra request.. EPSS estimates a 1.81% chance of exploitation in the next 30 days.

Description

HAProxy through 2.0.32, 2.1.x and 2.2.x through 2.2.30, 2.3.x and 2.4.x through 2.4.23, 2.5.x and 2.6.x before 2.6.15, 2.7.x before 2.7.10, and 2.8.x before 2.8.2 forwards empty Content-Length headers, violating RFC 9110 section 8.6. In uncommon cases, an HTTP/1 server behind HAProxy may interpret the payload as an extra request.

Metrics

CVSS 3.1

7.2/10

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

EPSS Probability

1.81%

75.9th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-444

Affected Software

Vendor	Product	Versions
Haproxy	Haproxy	<= 2.0.32
Haproxy	Haproxy	>= 2.2.0, <= 2.2.30
Haproxy	Haproxy	>= 2.4.0, <= 2.4.23
Haproxy	Haproxy	>= 2.5.0, < 2.6.15
Haproxy	Haproxy	>= 2.7.0, < 2.7.10
Haproxy	Haproxy	>= 2.8.0, < 2.8.2

References

https://cwe.mitre.org/data/definitions/436.htmlTechnical Description
https://github.com/haproxy/haproxy/commit/6492f1f29d738457ea9f382aca54537f35f9d856Patch
https://github.com/haproxy/haproxy/issues/2237Exploit, Issue Tracking, Vendor Advisory
https://www.haproxy.org/download/2.6/src/CHANGELOGRelease Notes
https://www.haproxy.org/download/2.7/src/CHANGELOGRelease Notes
https://www.haproxy.org/download/2.8/src/CHANGELOGRelease Notes
https://cwe.mitre.org/data/definitions/436.htmlTechnical Description
https://github.com/haproxy/haproxy/commit/6492f1f29d738457ea9f382aca54537f35f9d856Patch
https://github.com/haproxy/haproxy/issues/2237Exploit, Issue Tracking, Vendor Advisory
https://www.haproxy.org/download/2.6/src/CHANGELOGRelease Notes
https://www.haproxy.org/download/2.7/src/CHANGELOGRelease Notes
https://www.haproxy.org/download/2.8/src/CHANGELOGRelease Notes

Timeline

Published: Aug 10, 2023
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2023-40225?

How severe is CVE-2023-40225?

CVE-2023-40225 has a CVSS score of 7.2/10 (HIGH severity). The EPSS model estimates a 1.81% probability of exploitation in the next 30 days.

How do I fix CVE-2023-40225?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2023-40225?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST