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TI-2019-13285 Aliases CVE-2019-18277GHSA-7r84-r685-grmg

A flaw was found in HAProxy before 2.0.6.

Priority MEDIUM 45CWE-444Published · 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: 7 fixed, 2 without a fix

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

Summary

A flaw was found in HAProxy before 2.0.6. In legacy mode, messages featuring a transfer-encoding header missing the "chunked" value were not being correctly rejected. The impact was limited but if combined with the "http-reuse always" setting, it could be used to help construct an HTTP request smuggling attack against a vulnerable component employing a lenient parser that would ignore the content-length header as soon as it saw a transfer-encoding one (even if not entirely valid according to the specification).

Why it matters now

EPSS 0.10068 95th percentileScored 2026-11-07
Public exploit Yes 1 exploit referenceTagged by NVD
Fix Partial Red Hat: 4 advisoriesRed Hat: 7 fixed, 2 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 · 1

CPEVersionsRoleVendor
cpe:2.3:a:haproxy:haproxy:*:*:*:*:*:*:*:*before 2.0.6VulnerableHAProxy
  • cpe:2.3:a:haproxy:haproxy:*:*:*:*:*:*:*:* Versions before 2.0.6 Vulnerable ·HAProxy

Remediation

Red Hat 4 advisories

  • RHSA-2020:2265 Released 2020-05-26 · Red Hat rating Moderate
    rh-haproxy18-haproxy security, bug fix, and enhancement update
    • Red Hat Software Collections for Red Hat Enterprise Linux Server (v. 7) rh-haproxy18-haproxy-1.8.24-2.el7, rh-haproxy18-haproxy-syspaths-1.8.24-2.el7
    • Red Hat Software Collections for Red Hat Enterprise Linux Server EUS (v. 7.6) rh-haproxy18-haproxy-1.8.24-2.el7, rh-haproxy18-haproxy-syspaths-1.8.24-2.el7
    • Red Hat Software Collections for Red Hat Enterprise Linux Server EUS (v. 7.7) rh-haproxy18-haproxy-1.8.24-2.el7, rh-haproxy18-haproxy-syspaths-1.8.24-2.el7
    • Red Hat Software Collections for Red Hat Enterprise Linux Workstation (v. 7) rh-haproxy18-haproxy-1.8.24-2.el7, rh-haproxy18-haproxy-syspaths-1.8.24-2.el7
  • RHSA-2020:1936 Released 2020-05-04 · Red Hat rating Moderate
    OpenShift Container Platform 4.4.3 haproxy security update
    • Red Hat OpenShift Container Platform 4.4 haproxy-2.0.13-3.el7, haproxy-2.0.13-3.el8, haproxy20-2.0.13-3.el7 +1
  • RHSA-2020:1725 Released 2020-04-28 · Red Hat rating Moderate
    haproxy security, bug fix, and enhancement update
    • Red Hat Enterprise Linux AppStream (v. 8) haproxy-1.8.23-3.el8
Show 1 more Red Hat advisories
  • RHSA-2020:1287 Released 2020-04-07 · Red Hat rating Critical
    OpenShift Container Platform 3.11 security update
    • Red Hat OpenShift Container Platform 3.11 haproxy-1.8.23-3.el7, haproxy18-1.8.23-3.el7

Vendor assessments

Red Hat

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

ProductStatusPlan or fix
Red Hat OpenShift Container Platform 3.10AffectedNo fix planned: Will not fix
Red Hat OpenShift Container Platform 3.9AffectedNo fix planned: Will not fix
Red Hat Enterprise Linux AppStream (v. 8)Fixed RHSA-2020:1725
Red Hat OpenShift Container Platform 3.11Fixed RHSA-2020:1287
Red Hat OpenShift Container Platform 4.4Fixed RHSA-2020:1936
Red Hat Software Collections for Red Hat Enterprise Linux Server (v. 7)Fixed RHSA-2020:2265
Red Hat Software Collections for Red Hat Enterprise Linux Server EUS (v. 7.6)Fixed RHSA-2020:2265
Red Hat Software Collections for Red Hat Enterprise Linux Server EUS (v. 7.7)Fixed RHSA-2020:2265
Red Hat Software Collections for Red Hat Enterprise Linux Workstation (v. 7)Fixed RHSA-2020:2265
Not affected: 2 products
  • Red Hat Enterprise Linux 6
  • Red Hat Enterprise Linux 7

Timeline

  1. 2026-10-02 Threatist record created from CVE-2019-18277
  2. 2026-10-03 Alias added: GHSA-7r84-r685-grmg

References

Exploit 1

Advisory 3

Other 3

  • TI-2020-08973 In hpack_dht_insert in hpack-tbl.c in the HPACK decoder in HAProxy 1.8 through 2.x before… CVSS 3.1HIGH 8.8
  • TI-2023-21094 HAProxy through 2.0.32, 2.1.x and 2.2.x through 2.2.30, 2.3.x and 2.4.x through 2.4.23… CVSS 3.1HIGH 7.2
  • TI-2019-10602 HAProxy through 2.0.2 allows attackers to cause a denial of service (ha_panic) via… CVSS 3.0HIGH 7.5
  • TI-2021-17418 An integer overflow exists in HAProxy 2.0 through 2.5 in htx_add_header that can be… CVSS 3.1HIGH 7.5
  • TI-2016-04651 HAproxy 1.6.x before 1.6.6, when a deny comes from a reqdeny rule, allows remote… CVSS 3.0HIGH 7.5
  • TI-2026-25946 An issue was discovered in HAProxy before 3.3.6. CVSS 3.1MEDIUM 5.8
See all 35 →

Sources

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