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 important severity.

CVSS v3 Scores
CVSS detail CNA (VulnCheck) SUSE
Base Score 7.5 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:H/PR:N/UI:N/S:U/C:L/I:L/A:L
Attack Vector Network Network
Attack Complexity High High
Privileges Required None None
User Interaction None None
Scope Changed Unchanged
Confidentiality Impact Low Low
Integrity Impact High Low
Availability Impact None Low
CVSSv3 Version 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 [NEW]

No SUSE Security Announcements cross referenced.


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Please note that this evaluation state might be work in progress, incomplete or outdated.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 Affected
SUSE Linux Enterprise High Availability Extension 16.0 haproxy Affected
SUSE Linux Enterprise Micro 5.3 haproxy Affected
SUSE Linux Enterprise Micro 5.4 haproxy Affected
SUSE Linux Enterprise Micro 5.5 haproxy Affected
SUSE Linux Enterprise Server 16.1 haproxy Affected
SUSE Linux Enterprise Server for SAP applications 16.0 haproxy Affected
SUSE Linux Enterprise Server for SAP applications 16.1 haproxy Affected
SUSE Linux Micro 6.0 haproxy Affected
SUSE Linux Micro 6.1 haproxy Affected
SUSE Linux Micro 6.2 haproxy Affected
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 Affected
SUSE Linux Enterprise High Availability Extension 15 SP5 haproxy Affected
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 Affected
openSUSE Leap 15.4 haproxy Affected
openSUSE Leap 15.5 haproxy Affected
openSUSE Leap 15.6 haproxy Affected
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: Fri Jun 19 15:39:06 2026