An issue was discovered in dns.c in HAProxy through 1.8.14.
Priority MEDIUM 42CWE-835Published · Updated
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- Low
- Impact type
- Denial of service
- Confidentiality · integrity · availability
- None · None · High
- Fix status
- Partial Red Hat: 6 fixed, 3 without a fix
Attack profile from CVSS 3.0 · NVD. Fix status from CNA and Red Hat. Impact type from CWE-835.
Summary
An issue was discovered in dns.c in HAProxy through 1.8.14. In the case of a compressed pointer, a crafted packet can trigger infinite recursion by making the pointer point to itself, or create a long chain of valid pointers resulting in stack exhaustion.
Why it matters now
EPSS 0.06593 93rd percentileScored 2026-11-07
Fix Partial Red Hat: 1 advisoryRed Hat: 6 fixed, 3 without a fix
SSVC decision points
Not available: CISA has not published SSVC decision points for this record.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| — | — | all versions | — | No fix listed | CNA |
- — Vendor— Affected all versions Fixed in — No fix listed CNA
CPE configurations NVD · 5
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:a:haproxy:haproxy:*:*:*:*:*:*:*:* | up to 1.8.14 | Vulnerable | HAProxy |
| cpe:2.3:o:canonical:ubuntu_linux:16.04:*:*:*:lts:*:*:* | 16.04 | Vulnerable | Canonical |
| cpe:2.3:o:canonical:ubuntu_linux:18.04:*:*:*:lts:*:*:* | 18.04 | Vulnerable | Canonical |
| cpe:2.3:o:canonical:ubuntu_linux:18.10:*:*:*:*:*:*:* | 18.10 | Vulnerable | Canonical |
| cpe:2.3:a:redhat:openshift_container_platform:3.11:*:*:*:*:*:*:* | 3.11 | Vulnerable | Red Hat |
- cpe:2.3:a:haproxy:haproxy:*:*:*:*:*:*:*:* Versions up to 1.8.14 Vulnerable ·HAProxy
- cpe:2.3:o:canonical:ubuntu_linux:16.04:*:*:*:lts:*:*:* Versions 16.04 Vulnerable ·Canonical
- cpe:2.3:o:canonical:ubuntu_linux:18.04:*:*:*:lts:*:*:* Versions 18.04 Vulnerable ·Canonical
- cpe:2.3:o:canonical:ubuntu_linux:18.10:*:*:*:*:*:*:* Versions 18.10 Vulnerable ·Canonical
- cpe:2.3:a:redhat:openshift_container_platform:3.11:*:*:*:*:*:*:* Versions 3.11 Vulnerable ·Red Hat
Remediation
Red Hat 1 advisory
- RHSA-2019:1436 Released 2019-06-11 · Red Hat rating Moderaterh-haproxy18-haproxy security, bug fix, and enhancement update
- Red Hat Software Collections for Red Hat Enterprise Linux Server (v. 7) rh-haproxy18-haproxy-1.8.17-1.el7, rh-haproxy18-haproxy-syspaths-1.8.17-1.el7
- Red Hat Software Collections for Red Hat Enterprise Linux Server EUS (v. 7.4) rh-haproxy18-haproxy-1.8.17-1.el7, rh-haproxy18-haproxy-syspaths-1.8.17-1.el7
- Red Hat Software Collections for Red Hat Enterprise Linux Server EUS (v. 7.5) rh-haproxy18-haproxy-1.8.17-1.el7, rh-haproxy18-haproxy-syspaths-1.8.17-1.el7
- Red Hat Software Collections for Red Hat Enterprise Linux Server EUS (v. 7.6) rh-haproxy18-haproxy-1.8.17-1.el7, rh-haproxy18-haproxy-syspaths-1.8.17-1.el7
- Red Hat Software Collections for Red Hat Enterprise Linux Workstation (v. 7) rh-haproxy18-haproxy-1.8.17-1.el7, rh-haproxy18-haproxy-syspaths-1.8.17-1.el7
Vendor assessments
Red Hat
Red Hat rating: Important. Red Hat's page for this CVE →
| Product | Status | Plan or fix |
|---|---|---|
| Red Hat OpenShift Container Platform 3.10 | Affected | No fix yet |
| Red Hat OpenShift Container Platform 3.7 | Affected | No fix yet |
| Red Hat OpenShift Container Platform 3.9 | Affected | No fix yet |
| Red Hat OpenShift Container Platform 3.11 | Fixed | — |
| Red Hat Software Collections for Red Hat Enterprise Linux Server (v. 7) | Fixed | RHSA-2019:1436 |
| Red Hat Software Collections for Red Hat Enterprise Linux Server EUS (v. 7.4) | Fixed | RHSA-2019:1436 |
| Red Hat Software Collections for Red Hat Enterprise Linux Server EUS (v. 7.5) | Fixed | RHSA-2019:1436 |
| Red Hat Software Collections for Red Hat Enterprise Linux Server EUS (v. 7.6) | Fixed | RHSA-2019:1436 |
| Red Hat Software Collections for Red Hat Enterprise Linux Workstation (v. 7) | Fixed | RHSA-2019:1436 |
Not affected: 3 products
- Red Hat Enterprise Linux 6
- Red Hat Enterprise Linux 7
- Red Hat Enterprise Linux 8
Timeline
- 2026-10-02 Threatist record created from CVE-2018-20103
- 2026-10-03 Alias added: GHSA-c9xx-94cr-x7xm
References
Sources
- CVE-2018-20103 · CVE Program
- CVE-2018-20103 · NVD
- FIRST EPSS
- GHSA-c9xx-94cr-x7xm · GitHub Advisory Database · CC BY 4.0
- CVE-2018-20103 · Red Hat security data · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences