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TI-2021-17418 Aliases CVE-2021-40346GHSA-jwmg-q4wv-f75h

An integer overflow exists in HAProxy 2.0 through 2.5 in htx_add_header that can be…

Priority HIGH 67CWE-190Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
—
Confidentiality · integrity · availability
None · High · None
Fix status
Partial Red Hat: 4 fixed, 1 without a fix

Attack profile from CVSS 3.1 · NVD. Fix status from CNA and Red Hat.

Summary

An integer overflow exists in HAProxy 2.0 through 2.5 in htx_add_header that can be exploited to perform an HTTP request smuggling attack, allowing an attacker to bypass all configured http-request HAProxy ACLs and possibly other ACLs.

Why it matters now

EPSS 0.58832 99th percentileScored 2026-11-07
Public exploit Yes 1 exploit referenceTagged by NVD
Fix Partial Red Hat: 4 advisoriesRed Hat: 4 fixed, 1 without a fix

SSVC decision points

Not available: CISA has not published SSVC decision points for this record.

Affected products

VendorProductAffected versionsFixed inStatusSource
——all versions—No fix listedCNA
  • — Vendor— Affected all versions Fixed in — No fix listed CNA

CPE configurations NVD · 11

CPEVersionsRoleVendor
cpe:2.3:a:haproxy:haproxy:*:*:*:*:*:*:*:*2.0.0 to before 2.0.25; 2.2.0 to before 2.2.17; 2.3.0 to before 2.3.14; 2.4.0 to before 2.4.4VulnerableHAProxy
cpe:2.3:a:haproxy:haproxy:2.5:dev0:*:*:*:*:*:*2.5 dev0VulnerableHAProxy
cpe:2.3:a:haproxy:haproxy:2.5:dev1:*:*:*:*:*:*2.5 dev1VulnerableHAProxy
cpe:2.3:a:haproxy:haproxy:2.5:dev2:*:*:*:*:*:*2.5 dev2VulnerableHAProxy
cpe:2.3:a:haproxy:haproxy:2.5:dev3:*:*:*:*:*:*2.5 dev3VulnerableHAProxy
cpe:2.3:a:haproxy:haproxy:2.5:dev4:*:*:*:*:*:*2.5 dev4VulnerableHAProxy
cpe:2.3:a:haproxy:haproxy:2.5:dev5:*:*:*:*:*:*2.5 dev5VulnerableHAProxy
cpe:2.3:a:haproxy:haproxy:2.5:dev6:*:*:*:*:*:*2.5 dev6VulnerableHAProxy
cpe:2.3:o:debian:debian_linux:11.0:*:*:*:*:*:*:*11.0VulnerableDebian
cpe:2.3:o:fedoraproject:fedora:33:*:*:*:*:*:*:*33VulnerableFedoraproject
  • cpe:2.3:a:haproxy:haproxy:*:*:*:*:*:*:*:* Versions 2.0.0 to before 2.0.25; 2.2.0 to before 2.2.17; 2.3.0 to before 2.3.14; 2.4.0 to before 2.4.4 Vulnerable ·HAProxy
  • cpe:2.3:a:haproxy:haproxy:2.5:dev0:*:*:*:*:*:* Versions 2.5 dev0 Vulnerable ·HAProxy
  • cpe:2.3:a:haproxy:haproxy:2.5:dev1:*:*:*:*:*:* Versions 2.5 dev1 Vulnerable ·HAProxy
  • cpe:2.3:a:haproxy:haproxy:2.5:dev2:*:*:*:*:*:* Versions 2.5 dev2 Vulnerable ·HAProxy
  • cpe:2.3:a:haproxy:haproxy:2.5:dev3:*:*:*:*:*:* Versions 2.5 dev3 Vulnerable ·HAProxy
  • cpe:2.3:a:haproxy:haproxy:2.5:dev4:*:*:*:*:*:* Versions 2.5 dev4 Vulnerable ·HAProxy
  • cpe:2.3:a:haproxy:haproxy:2.5:dev5:*:*:*:*:*:* Versions 2.5 dev5 Vulnerable ·HAProxy
  • cpe:2.3:a:haproxy:haproxy:2.5:dev6:*:*:*:*:*:* Versions 2.5 dev6 Vulnerable ·HAProxy
  • cpe:2.3:o:debian:debian_linux:11.0:*:*:*:*:*:*:* Versions 11.0 Vulnerable ·Debian
  • cpe:2.3:o:fedoraproject:fedora:33:*:*:*:*:*:*:* Versions 33 Vulnerable ·Fedoraproject
Show 1 more CPE
CPEVersionsRoleVendor
cpe:2.3:o:fedoraproject:fedora:34:*:*:*:*:*:*:*34VulnerableFedoraproject
  • cpe:2.3:o:fedoraproject:fedora:34:*:*:*:*:*:*:* Versions 34 Vulnerable ·Fedoraproject

Remediation

Red Hat 4 advisories

  • RHSA-2022:0114 Released 2022-01-19 · Red Hat rating Moderate
    OpenShift Container Platform 4.7.41 security update
    • Red Hat OpenShift Container Platform 4.7 haproxy-2.0.19-2.el7, haproxy-2.0.19-2.el8, haproxy20-2.0.19-2.el7 +1
  • RHSA-2022:0024 Released 2022-01-12 · Red Hat rating Moderate
    OpenShift Container Platform 4.6.53 security update
    • Red Hat OpenShift Container Platform 4.6 haproxy-2.0.16-2.el7, haproxy-2.0.16-4.el8, haproxy20-2.0.16-2.el7 +1
  • RHSA-2021:5208 Released 2022-01-05 · Red Hat rating Moderate
    OpenShift Container Platform 4.8.25 security update
    • Red Hat OpenShift Container Platform 4.8 haproxy-2.2.13-2.el7, haproxy-2.2.13-2.el8
Show 1 more Red Hat advisories
  • RHSA-2021:4118 Released 2021-11-10 · Red Hat rating Moderate
    OpenShift Container Platform 4.9.6 packages and security update
    • Red Hat OpenShift Container Platform 4.9 haproxy-2.2.15-2.el8

Vendor assessments

Red Hat

Red Hat rating: Moderate. Red Hat's page for this CVE →

ProductStatusPlan or fix
Red Hat OpenShift Container Platform 3.11AffectedNo fix planned: Out of support scope
Red Hat OpenShift Container Platform 4.6Fixed RHSA-2022:0024
Red Hat OpenShift Container Platform 4.7Fixed RHSA-2022:0114
Red Hat OpenShift Container Platform 4.8Fixed RHSA-2021:5208
Red Hat OpenShift Container Platform 4.9Fixed RHSA-2021:4118
Not affected: 9 products
  • Red Hat Enterprise Linux 6
  • Red Hat Enterprise Linux 7
  • Red Hat Enterprise Linux 8
  • Red Hat Enterprise Linux 9
  • Red Hat OpenShift Container Platform 4.6
  • Red Hat OpenShift Container Platform 4.7
  • Red Hat OpenShift Container Platform 4.8
  • Red Hat OpenShift Container Platform 4.9
  • Red Hat Software Collections

Timeline

  1. 2026-10-02 Threatist record created from CVE-2021-40346
  2. 2026-10-03 Alias added: GHSA-jwmg-q4wv-f75h

References

Exploit 1

Patch 2

Advisory 3

Other 4

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences