CVE-2023-0836
highpriority · track · 30EPSS 0.012 · 68 %ileDEEURUUSEPSS · scored 2026-10-27
An information leak vulnerability was discovered in HAProxy 2.1, 2.2 before 2.2.27, 2.3, 2.4 before 2.4.21, 2.5 before 2.5.11, 2.6 before 2.6.8, 2.7 before 2.7.1. There are 5 bytes left uninitialized in the connection buffer when encoding the FCGI_BEGIN_REQUEST record. Sensitive data may be disclosed to configured FastCGI backends in an unexpected way.
remediations
Vendor fix, mitigation, or workaround guidance, as published by each source.
A vendor fix is available.
- Fixedhaproxy-0:2.4.22-1.el9.aarch64 as a component of Red Hat Enterprise Linux AppStream (v. 9)redhat_csaf
For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258
https://access.redhat.com/errata/RHSA-2023:6496 - Fixedhaproxy-0:2.4.22-1.el9.ppc64le as a component of Red Hat Enterprise Linux AppStream (v. 9)redhat_csaf
For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258
https://access.redhat.com/errata/RHSA-2023:6496 - Fixedhaproxy-0:2.4.22-1.el9.s390x as a component of Red Hat Enterprise Linux AppStream (v. 9)redhat_csaf
For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258
https://access.redhat.com/errata/RHSA-2023:6496 - Fixedhaproxy-0:2.4.22-1.el9.src as a component of Red Hat Enterprise Linux AppStream (v. 9)redhat_csaf
For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258
https://access.redhat.com/errata/RHSA-2023:6496 - Fixedhaproxy-0:2.4.22-1.el9.x86_64 as a component of Red Hat Enterprise Linux AppStream (v. 9)redhat_csaf
For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258
https://access.redhat.com/errata/RHSA-2023:6496 - Fixedhaproxy-debuginfo-0:2.4.22-1.el9.aarch64 as a component of Red Hat Enterprise Linux AppStream (v. 9)redhat_csaf
For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258
https://access.redhat.com/errata/RHSA-2023:6496 - Fixedhaproxy-debuginfo-0:2.4.22-1.el9.ppc64le as a component of Red Hat Enterprise Linux AppStream (v. 9)redhat_csaf
For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258
https://access.redhat.com/errata/RHSA-2023:6496 - Fixedhaproxy-debuginfo-0:2.4.22-1.el9.s390x as a component of Red Hat Enterprise Linux AppStream (v. 9)redhat_csaf
For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258
https://access.redhat.com/errata/RHSA-2023:6496 - Fixedhaproxy-debuginfo-0:2.4.22-1.el9.x86_64 as a component of Red Hat Enterprise Linux AppStream (v. 9)redhat_csaf
For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258
https://access.redhat.com/errata/RHSA-2023:6496 - Fixedhaproxy-debugsource-0:2.4.22-1.el9.aarch64 as a component of Red Hat Enterprise Linux AppStream (v. 9)redhat_csaf
For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258
https://access.redhat.com/errata/RHSA-2023:6496 - Fixedhaproxy-debugsource-0:2.4.22-1.el9.ppc64le as a component of Red Hat Enterprise Linux AppStream (v. 9)redhat_csaf
For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258
https://access.redhat.com/errata/RHSA-2023:6496 - Fixedhaproxy-debugsource-0:2.4.22-1.el9.s390x as a component of Red Hat Enterprise Linux AppStream (v. 9)redhat_csaf
For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258
https://access.redhat.com/errata/RHSA-2023:6496 - Fixedhaproxy-debugsource-0:2.4.22-1.el9.x86_64 as a component of Red Hat Enterprise Linux AppStream (v. 9)redhat_csaf
For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258
https://access.redhat.com/errata/RHSA-2023:6496
cvss
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 6.9–7.5
ssvc
A stakeholder decision — act, attend, or track — from exploitation and impact.
weaknesses
The CWE weakness classes this flaw belongs to.
affected products (47)
Products and version ranges known to be affected.
- n/a haproxy≤ HAProxy 2.8, HAProxy 2.7.1, HAProxy 2.6.8, HAProxy 2.5.11, HAProxy 2.4.21, HAProxy 2.2.27enisa_euvdEU
advisories (3)
Vendor and ecosystem advisories describing this.
- RHSA-2023:6496Red Hat Security Advisory: haproxy security and bug fix update2023-11-07csaf · redhat_csafUS
An update for haproxy is now available for Red Hat Enterprise Linux 9. Red Hat Product Security has rated this update as having a security impact of Moderate. A Common Vulnerability Scoring System (CVSS) base score, which gives a detailed severity rating, is available for each vulnerability from the CVE link(s) in the References section.
- WID-SEC-W-2023-0716HAProxy Enterprise: Schwachstelle ermöglicht Offenlegung von InformationenDeutsch2023-03-22csaf · cert_bundDE
Ein entfernter, anonymer Angreifer kann eine Schwachstelle in HAProxy Enterprise ausnutzen, um Informationen offenzulegen.
- BIT-haproxy-2023-08362024-03-06vendor · osvUS
An information leak vulnerability was discovered in HAProxy 2.1, 2.2 before 2.2.27, 2.3, 2.4 before 2.4.21, 2.5 before 2.5.11, 2.6 before 2.6.8, 2.7 before 2.7.1. There are 5 bytes left uninitialized in the connection buffer when encoding the FCGI_BEGIN_REQUEST record. Sensitive data may be disclosed to configured FastCGI backends in an unexpected way.
also known as (4)
Other names and identifiers for this entity.
sources
Which sources assert this record, and when.
references (9)
External citations — patches, advisories, analysis.
- https://cxsecurity.com/cveshow/CVE-2023-0836/cnnvd
- https://git.haproxy.org/?p=haproxy.git;a=commitdiff;h=2e6bf0acnnvd
- https://www.auscert.org.au/bulletins/ESB-2023.1933cnnvd
- https://www.auscert.org.au/bulletins/ESB-2023.2148cnnvd
- https://www.debian.org/security/2023/dsa-5388cnnvd
- https://git.haproxy.org/?p=haproxy.git%3Ba=commitdiff%3Bh=2e6bf0aenisa_euvd
- https://www.debian.org/security/2023/dsa-5388enisa_euvd
- https://git.haproxy.org/?p=haproxy.git%3Ba=commitdiff%3Bh=2e6bf0anvd
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