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Public proof of conceptFix available

CVE-2023-40225

A public proof of concept exists; no exploitation attested.

  • Published2023-08-10
  • Fixed in2.8.2 · 2.7.10 · 2.6.15 · 2.4.24 · 2.2.31 · 2.0.33
  • WeaknessCWE-444

Am I affected?

With a domain, we read the version its public headers and pages expose. A distribution build can carry the fix under an older number.

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.

Timeline

dates in UTC
  1. 2023-08-1021:15CVE publishedNVD

Versions per branch

NVD · OSV
HAProxy
BranchAffectedFixed in
2.8≥ 2.8.0, < 2.8.22.8.2
2.7≥ 2.7.0, < 2.7.102.7.10
2.x≥ 2.5.0, < 2.6.152.6.15
2.4≥ 2.4.0, < 2.4.242.4.24
2.2≥ 2.2.0, < 2.2.312.2.31
2.0< 2.0.332.0.33
2.0≤ 2.0.32no fix published
2.2≥ 2.2.0, ≤ 2.2.30no fix published
2.4≥ 2.4.0, ≤ 2.4.23no fix published

as publishedRanges as NVD and OSV publish them; a distribution’s build can be fixed under an older number.

Distribution builds and vendor advisories

Packages from OSV.dev and products from the vendors' CSAF advisories.

version not verifiedVersions not verified: read as OSV.dev and the vendors publish them, not checked against each vendor's release list.

Packages

  • haproxyUbuntu:22.04:LTSall versions · fixed in 2.4.22-0ubuntu0.22.04.2
  • haproxyUbuntu:20.04:LTSall versions · fixed in 2.0.31-0ubuntu0.2
  • haproxyTuxCare:AlmaLinux:9.2all versions · fixed in 2.4.17-6.el9.tuxcare.els3
  • haproxySUSE:Linux Enterprise Micro 5.4all versions · fixed in 2.4.22+git0.f8e3218e2-150400.3.16.1
  • haproxySUSE:Linux Enterprise Micro 5.3all versions · fixed in 2.4.22+git0.f8e3218e2-150400.3.16.1
  • haproxySUSE:Linux Enterprise High Availability Extension 15 SP5all versions · fixed in 2.4.22+git0.f8e3218e2-150400.3.16.1
  • haproxySUSE:Linux Enterprise High Availability Extension 15 SP4all versions · fixed in 2.4.22+git0.f8e3218e2-150400.3.16.1
  • haproxySUSE:Linux Enterprise High Availability Extension 15 SP3all versions · fixed in 2.0.31-150200.11.23.1

26 more package ranges on OSV.dev

Vendor advisories

  • CVE-2023-40225 Red Hat Product Security78 products fixed · 11 known affected

    haproxy: Proxy forwards malformed empty Content-Length headers

    haproxy.src as a component of Red Hat Ceph Storage 5 · haproxy22 as a component of Red Hat Ceph Storage 5 · haproxy as a component of Red Hat Enterprise Linux 6 · +8 more

  • RHSA-2024:1142 Red Hat Product Security13 products fixed

    Red Hat Security Advisory: haproxy security update

  • RHSA-2024:1089 Red Hat Product Security13 products fixed

    Red Hat Security Advisory: haproxy security update

  • RHSA-2024:0308 Red Hat Product Security13 products fixed

    Red Hat Security Advisory: OpenShift Container Platform 4.11.57 packages and security update

  • RHSA-2024:0200 Red Hat Product Security13 products fixed

    Red Hat Security Advisory: OpenShift Container Platform 4.12.47 security update

  • RHSA-2023:7606 Red Hat Product Security13 products fixed

    Red Hat Security Advisory: OpenShift Container Platform 4.13.25 packages and security update

1 more advisory

Full record on NVD

Fix

  1. Update HAProxy to 2.8.2 · 2.7.10 · 2.6.15 · 2.4.24 · 2.2.31 · 2.0.33
  2. Vendor fix Red Hat Product Security RHSA-2024:1142 · 13 productsFor details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258
  3. Vendor fix Red Hat Product Security RHSA-2024:0308 · 13 productsFor OpenShift Container Platform 4.11 see the following documentation, which will be updated shortly for this release, for important instructions on how to upgrade your cluster and fully apply this asynchronous errata update: https://docs.openshift.com/container-platform/4.11/release_notes/ocp-4-1…
  4. Vendor fix Red Hat Product Security RHSA-2024:0200 · 13 productsSee the following documentation, which will be updated shortly for this release, for important instructions on how to upgrade your cluster and fully apply this asynchronous errata update: https://docs.openshift.com/container-platform/4.12/release_notes/ocp-4-12-release-notes.html Details on how t…
  5. Vendor fix Red Hat Product Security RHSA-2023:7606 · 13 productsFor OpenShift Container Platform 4.13 see the following documentation, which will be updated shortly for this release, for important instructions on how to upgrade your cluster and fully apply this asynchronous errata update: https://docs.openshift.com/container-platform/4.13/release_notes/ocp-4-1…
  6. Vendor fix Red Hat Product Security RHSA-2023:7473 · 13 productsFor OpenShift Container Platform 4.14 see the following documentation, which will be updated shortly for this release, for important instructions on how to upgrade your cluster and fully apply this asynchronous errata update: https://docs.openshift.com/container-platform/4.14/release_notes/ocp-4-1…
  7. Workaround from the vendor Red Hat Product Security RHSA-2024:1142 · 13 productsThis flaw can be mitigated by applying a rule to explicitly reject any requests with an empty Content-Lenght header. The following line can be added to any frontend configurations at the /etc/haproxy/haproxy.cfg file. ~~~ http-request deny if { hdr_len(content-length) 0 } ~~~

Advisories and patches

Detection

Nuclei template
none so far
ProjectDiscovery
Exploit-DB
no entry
Exploit-DB
Proof of concept
Metasploit modules
none listed
Metasploit Framework

Sources

Identifiers

Technical details

CVSS v3 Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N
Published
2023-08-10
Last Modified
2026-06-17
NVD status
Modified
GitHub Advisory
GHSA-xgq7-jp95-v2qv

Frequently asked questions

What is CVE-2023-40225?

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.

Is CVE-2023-40225 actively exploited?

A proof-of-concept exploit exists for CVE-2023-40225, but active exploitation has not been confirmed at this time.

What is the CVSS score for CVE-2023-40225?

CVE-2023-40225 has a CVSS v3 base score of 7.2 (HIGH severity), with vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N.

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