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TI-2021-16627 Aliases CVE-2021-39242GHSA-gh3m-9h22-r3r5

An issue was discovered in HAProxy 2.2 before 2.2.16, 2.3 before 2.3.13, and 2.4 before…

Priority LOW 37CWE-755Published · 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: 2 fixed, 1 without a fix

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

Summary

An issue was discovered in HAProxy 2.2 before 2.2.16, 2.3 before 2.3.13, and 2.4 before 2.4.3. It can lead to a situation with an attacker-controlled HTTP Host header, because a mismatch between Host and authority is mishandled.

Why it matters now

EPSS 0.02231 82nd percentileScored 2026-11-07
Fix Partial Red Hat: 2 advisoriesRed Hat: 2 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 · 4

CPEVersionsRoleVendor
cpe:2.3:a:haproxy:haproxy:*:*:*:*:*:*:*:*2.2.0 to before 2.2.16; 2.3.0 to before 2.3.13; 2.4.0 to before 2.4.3VulnerableHAProxy
cpe:2.3:o:debian:debian_linux:11.0:*:*:*:*:*:*:*11.0VulnerableDebian
cpe:2.3:o:fedoraproject:fedora:33:*:*:*:*:*:*:*33VulnerableFedoraproject
cpe:2.3:o:fedoraproject:fedora:34:*:*:*:*:*:*:*34VulnerableFedoraproject
  • cpe:2.3:a:haproxy:haproxy:*:*:*:*:*:*:*:* Versions 2.2.0 to before 2.2.16; 2.3.0 to before 2.3.13; 2.4.0 to before 2.4.3 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
  • cpe:2.3:o:fedoraproject:fedora:34:*:*:*:*:*:*:* Versions 34 Vulnerable ·Fedoraproject

Remediation

Red Hat 2 advisories

  • 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
  • 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 4.8Fixed RHSA-2021:5208
Red Hat OpenShift Container Platform 4.9Fixed RHSA-2021:4118
Not affected: 7 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 4.8
  • Red Hat OpenShift Container Platform 4.9
  • Red Hat Software Collections

Timeline

  1. 2026-10-02 Threatist record created from CVE-2021-39242
  2. 2026-10-03 Alias added: GHSA-gh3m-9h22-r3r5

References

Advisory 3

Other 2

Sources

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