Upstream information

CVE-2026-55203 at MITRE

Description

HAProxy through 3.4.0, fixed in commit 5985276, contains an integer overflow vulnerability in the fcgi_conn structure's drl field that allows buffer misparse as new FCGI record headers. When contentLength is 65535 and paddingLength is 1 or more, the drl field wraps to 0, causing incorrect record consumption and allowing malicious FastCGI backends to desynchronize the FCGI framing parser, potentially causing request routing errors, response smuggling, or memory safety issues.

Other Security Trackers

SUSE information

Overall state of this security issue: Pending

This issue is currently rated as having moderate severity.

CVSS v3 Scores
CVSS detail CNA (VulnCheck) National Vulnerability Database SUSE
Base Score 7.5 9.1 5.6
Vector CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:L/I:H/A:N CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:L
Attack Vector Network Network Network
Attack Complexity High Low High
Privileges Required None None None
User Interaction None None None
Scope Changed Unchanged Unchanged
Confidentiality Impact Low None Low
Integrity Impact High High Low
Availability Impact None High Low
CVSSv3 Version 3.1 3.1 3.1
CVSS v4 Scores
CVSS detail CNA (VulnCheck)
Base Score 9
Vector CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:H/VA:N/SC:L/SI:H/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
Attack Vector Network
Attack Complexity Low
Attack Requirements Present
Privileges Required None
User Interaction None
Vulnerable System Confidentiality Impact None
Vulnerable System Integrity Impact High
Vulnerable System Availability Impact None
Subsequent System Confidentiality Impact Low
Subsequent System Integrity Impact High
Subsequent System Availability Impact None
CVSSv4 Version 4.0
SUSE Bugzilla entry: 1268557 [IN_PROGRESS]

SUSE Security Advisories:

List of released packages

Product(s) Fixed package version(s) References
Image SLE-Micro
Image SLE-Micro-Azure
Image SLE-Micro-BYOS
Image SLE-Micro-BYOS-Azure
Image SLE-Micro-BYOS-EC2
Image SLE-Micro-BYOS-GCE
Image SLE-Micro-EC2
Image SLE-Micro-GCE
  • libgnutls30 >= 3.8.3-6.1
SUSE Linux Enterprise High Availability Extension 15 SP4
  • haproxy >= 2.4.22+git0.f8e3218e2-150400.3.28.1
 Patchnames:
SUSE-SLE-Product-HA-15-SP4-2026-2651
SUSE Linux Enterprise High Availability Extension 15 SP5
  • haproxy >= 2.4.22+git0.f8e3218e2-150400.3.28.1
 Patchnames:
SUSE-SLE-Product-HA-15-SP5-2026-2651
SUSE Linux Enterprise High Availability Extension 15 SP6
  • haproxy >= 2.8.11+git0.01c1056a4-150600.3.15.1
 Patchnames:
SUSE-SLE-Product-HA-15-SP6-2026-2652
SUSE Linux Enterprise High Availability Extension 15 SP7
  • haproxy >= 2.8.11+git0.01c1056a4-150600.3.15.1
 Patchnames:
SUSE-SLE-Product-HA-15-SP7-2026-2652
SUSE Linux Enterprise Micro 5.3
  • haproxy >= 2.4.22+git0.f8e3218e2-150400.3.28.1
 Patchnames:
SUSE-SLE-Micro-5.3-2026-2651
SUSE Linux Enterprise Micro 5.4
  • haproxy >= 2.4.22+git0.f8e3218e2-150400.3.28.1
 Patchnames:
SUSE-SLE-Micro-5.4-2026-2651
SUSE Linux Enterprise Micro 5.5
  • haproxy >= 2.4.22+git0.f8e3218e2-150400.3.28.1
 Patchnames:
SUSE-SLE-Micro-5.5-2026-2651
SUSE Linux Micro 6.0
  • haproxy >= 2.8.11+git0.01c1056a4-4.1
 Patchnames:
SUSE-SLE-Micro-6.0-781
openSUSE Leap 16.0
  • haproxy >= 3.2.21+git0.dbe43be37-160000.1.1
 Patchnames:
openSUSE-Leap-16.0-1166
openSUSE Tumbleweed
  • haproxy >= 3.4.0+git31.fc300e9f2-1.1
 Patchnames:
openSUSE-Tumbleweed-2026-11090

List of packages in QA

Product(s) Package(s)
SUSE Linux Enterprise Server for SAP applications 16.0
  • haproxy >= 3.2.21+git0.dbe43be37-160000.1.1
SUSE Linux Micro 6.2
  • haproxy >= 3.2.21+git0.dbe43be37-160000.1.1

Status of this issue by product and package

Please note that this evaluation state might be work in progress, incomplete or outdated. Also information for service packs in the LTSS phase is only included for issues meeting the LTSS criteria. If in doubt, feel free to contact us for clarification. The updates are grouped by state of their lifecycle. SUSE product lifecycles are documented on the lifecycle page.

Product(s) Source package State
Products under general support and receiving all security fixes.
SUSE Linux Enterprise High Availability Extension 15 SP7 haproxy Released
SUSE Linux Enterprise High Availability Extension 16.0 haproxy Affected
SUSE Linux Enterprise Micro 5.3 haproxy Released
SUSE Linux Enterprise Micro 5.4 haproxy Released
SUSE Linux Enterprise Micro 5.5 haproxy Released
SUSE Linux Enterprise Micro for Rancher 5.3 haproxy Released
SUSE Linux Enterprise Micro for Rancher 5.4 haproxy Released
SUSE Linux Enterprise Server 16.1 haproxy Affected
SUSE Linux Enterprise Server for SAP applications 16.0 haproxy In progress
SUSE Linux Enterprise Server for SAP applications 16.1 haproxy Affected
SUSE Linux Micro 6.0 haproxy Released
SUSE Linux Micro 6.1 haproxy Released
SUSE Linux Micro 6.2 haproxy In progress
openSUSE Leap 16.0 haproxy Affected
Products under Long Term Service Pack support and receiving important and critical security fixes.
SUSE Linux Enterprise High Availability Extension 12 SP5 haproxy Not affected
SUSE Linux Enterprise High Availability Extension 15 SP4 haproxy Released
SUSE Linux Enterprise High Availability Extension 15 SP5 haproxy Released
SUSE Linux Enterprise Server for SAP Applications 12 SP5 haproxy Not affected
Products past their end of life and not receiving proactive updates anymore.
SUSE Linux Enterprise High Availability Extension 15 SP6 haproxy Released
openSUSE Leap 15.4 haproxy Released
openSUSE Leap 15.5 haproxy Affected
openSUSE Leap 15.6 haproxy Released
openSUSE Leap Micro 5.3 haproxy Affected
openSUSE Leap Micro 5.4 haproxy Affected
openSUSE Leap Micro 5.5 haproxy Affected

SUSE Timeline for this CVE

CVE page created: Thu Jun 18 20:07:56 2026
CVE page last modified: Wed Jul 8 21:33:58 2026