CVE-2018-20102
An out-of-bounds read in dns_validate_dns_response in dns.c was discovered in HAProxy through 1.8...
An out-of-bounds read in dns_validate_dns_response in dns.c was discovered in HAProxy through 1.8.14. Due to a missing check when validating DNS responses, remote attackers might be able read the 16 bytes corresponding to an AAAA record from the non-initialized part of the buffer, possibly accessing anything that was left on the stack, or even past the end of the 8193-byte buffer, depending on the value of accepted_payload_size.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- High
- Integrity
- None
- Availability
- None
Exploit likelihood
What each source reports
NVD Score used
An out-of-bounds read in dns_validate_dns_response in dns.c was discovered in HAProxy through 1.8.14. Due to a missing check when validating DNS responses, remote attackers might be able read the 16 bytes corresponding to an AAAA record from the non-initialized part of the buffer, possibly accessing anything that was left on the stack, or even past the end of the 8193-byte buffer, depending on the value of accepted_payload_size.
- Record
CVE-2018-20102- CVSS 3.0
- 7.5 High
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N - CVSS 2.0
- 5.0 Medium
AV:N/AC:L/Au:N/C:P/I:N/A:N - Weakness
- CWE-125
- Updated
- 2026-11-02
CVE List No score
An out-of-bounds read in dns_validate_dns_response in dns.c was discovered in HAProxy through 1.8.14. Due to a missing check when validating DNS responses, remote attackers might be able read the 16 bytes corresponding to an AAAA record from the non-initialized part of the buffer, possibly accessing anything that was left on the stack, or even past the end of the 8193-byte buffer, depending on the value of accepted_payload_size.
- Record
CVE-2018-20102- Updated
- 2026-11-02
EUVDEUVD-2018-12672 No score
An out-of-bounds read in dns_validate_dns_response in dns.c was discovered in HAProxy through 1.8.14. Due to a missing check when validating DNS responses, remote attackers might be able read the 16 bytes corresponding to an AAAA record from the non-initialized part of the buffer, possibly accessing anything that was left on the stack, or even past the end of the 8193-byte buffer, depending on the value of accepted_payload_size.
- Record
EUVD-2018-12672- Updated
- 2026-11-03
GitHub AdvisoriesGHSA-5m22-hqfx-435p
An out-of-bounds read in dns_validate_dns_response in dns.c was discovered in HAProxy through 1.8...
An out-of-bounds read in dns_validate_dns_response in dns.c was discovered in HAProxy through 1.8.14. Due to a missing check when validating DNS responses, remote attackers might be able read the 16 bytes corresponding to an AAAA record from the non-initialized part of the buffer, possibly accessing anything that was left on the stack, or even past the end of the 8193-byte buffer, depending on the value of accepted_payload_size.
- Record
GHSA-5m22-hqfx-435p- CVSS 3.0
- 7.5 High
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N - Weakness
- CWE-125
- Updated
- 2026-11-02
OSV
An out-of-bounds read in dns_validate_dns_response in dns.c was discovered in HAProxy through 1.8.14. Due to a missing check when validating DNS responses, remote attackers might be able read the 16 bytes corresponding to an AAAA record from the non-initialized part of the buffer, possibly accessing anything that was left on the stack, or even past the end of the 8193-byte buffer, depending on the value of accepted_payload_size.
- Record
CVE-2018-20102- CVSS 3.0
- 7.5 High
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N - Updated
- 2026-11-02
OSVDEBIAN-CVE-2018-20102
An out-of-bounds read in dns_validate_dns_response in dns.c was discovered in HAProxy through 1.8.14. Due to a missing check when validating DNS responses, remote attackers might be able read the 16 bytes corresponding to an AAAA record from the non-initialized part of the buffer, possibly accessing anything that was left on the stack, or even past the end of the 8193-byte buffer, depending on the value of accepted_payload_size.
- Record
DEBIAN-CVE-2018-20102- CVSS 3.0
- 7.5 High
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N - Updated
- 2026-11-02
Show 7 moreShow less
OSVRHBA-2019:0326
Red Hat Bug Fix Advisory: OpenShift Container Platform 3.11 bug fix update
- Record
RHBA-2019:0326- CVSS 3.0
- 8.8 High
CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H - Updated
- 2026-11-02
OSVRHSA-2019:0547
Red Hat Security Advisory: OpenShift Container Platform 3.9 haproxy security update
- Record
RHSA-2019:0547- CVSS 3.0
- 6.5 Medium
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:L - Updated
- 2026-11-02
OSVRHSA-2019:1436
Red Hat Security Advisory: rh-haproxy18-haproxy security, bug fix, and enhancement update
- Record
RHSA-2019:1436- CVSS 3.0
- 7.5 High
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - Updated
- 2026-11-02
OSVUBUNTU-CVE-2018-20102
An out-of-bounds read in dns_validate_dns_response in dns.c was discovered in HAProxy through 1.8.14. Due to a missing check when validating DNS responses, remote attackers might be able read the 16 bytes corresponding to an AAAA record from the non-initialized part of the buffer, possibly accessing anything that was left on the stack, or even past the end of the 8193-byte buffer, depending on the value of accepted_payload_size.
- Record
UBUNTU-CVE-2018-20102- CVSS 3.0
- 7.5 High
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N - Updated
- 2026-11-02
OSVopenSUSE-SU-2019:0044-1 No score
Security update for haproxy
This update for haproxy to version 1.8.15 fixes the following issues:
Security issues fixed:
- CVE-2018-20102: Fixed an out-of-bounds read in dns_validate_dns_response(), which allowed for memory disclosure (bsc#1119368)
- CVE-2018-20103: Fixed an infinite recursion via crafted packet allows stack exhaustion and denial of service (bsc#1119419)
Other notable bug fixes:
- Fix off-by-one write in dns_validate_dns_response()
- Fix out-of-bounds read via signedness error in dns_validate_dns_response()
- Prevent out-of-bounds read in dns_validate_dns_response()
- Prevent out-of-bounds read in dns_read_name()
- Prevent stack-exhaustion via recursion loop in dns_read_name
For a full list of changes, please refer to: https://www.haproxy.org/download/1.8/src/CHANGELOG
This update was imported from the SUSE:SLE-15:Update update project.
- Record
openSUSE-SU-2019:0044-1- Updated
- 2026-11-02
OSVSUSE-SU-2019:0061-1 No score
Security update for haproxy
This update for haproxy to version 1.8.15 fixes the following issues:
Security issues fixed:
- CVE-2018-20102: Fixed an out-of-bounds read in dns_validate_dns_response(), which allowed for memory disclosure (bsc#1119368)
- CVE-2018-20103: Fixed an infinite recursion via crafted packet allows stack exhaustion and denial of service (bsc#1119419)
Other notable bug fixes:
- Fix off-by-one write in dns_validate_dns_response()
- Fix out-of-bounds read via signedness error in dns_validate_dns_response()
- Prevent out-of-bounds read in dns_validate_dns_response()
- Prevent out-of-bounds read in dns_read_name()
- Prevent stack-exhaustion via recursion loop in dns_read_name
For a full list of changes, please refer to: https://www.haproxy.org/download/1.8/src/CHANGELOG
- Record
SUSE-SU-2019:0061-1- Updated
- 2026-11-02
OSVUSN-3858-1 No score
haproxy vulnerabilities
It was discovered that HAProxy incorrectly handled certain requests. An attacker could possibly use this to expose sensitive information. (CVE-2018-20102)
It was discovered that HAProxy incorrectly handled certain requests. A attacker could possibly use this issue to cause a denial of service. This issue only affected Ubuntu 18.04 LTS and Ubuntu 18.10. (CVE-2018-20103, CVE-2018-20615)
- Record
USN-3858-1- Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
haproxyDebian:12 |
before 1.8.15-1 | 1.8.15-1 |
haproxyDebian:13 |
before 1.8.15-1 | 1.8.15-1 |
haproxyDebian:14 |
before 1.8.15-1 | 1.8.15-1 |
haproxyDebian:9 |
before 1.7.5-2+deb9u1, plus listed versions 1.7.5-2 |
1.7.5-2+deb9u1 |
atomic-enterprise-service-catalogRed Hat:openshift:3.11::el7 |
before 1:3.11.82-1.git.1673.133961e.el7 | 1:3.11.82-1.git.1673.133961e.el7 |
atomic-enterprise-service-catalog-svcatRed Hat:openshift:3.11::el7 |
before 1:3.11.82-1.git.1673.133961e.el7 | 1:3.11.82-1.git.1673.133961e.el7 |
atomic-openshiftRed Hat:openshift:3.11::el7 |
before 0:3.11.82-1.git.0.08bc31b.el7 | 0:3.11.82-1.git.0.08bc31b.el7 |
atomic-openshift-clientsRed Hat:openshift:3.11::el7 |
before 0:3.11.82-1.git.0.08bc31b.el7 | 0:3.11.82-1.git.0.08bc31b.el7 |
atomic-openshift-clients-redistributableRed Hat:openshift:3.11::el7 |
before 0:3.11.82-1.git.0.08bc31b.el7 | 0:3.11.82-1.git.0.08bc31b.el7 |
atomic-openshift-cluster-autoscalerRed Hat:openshift:3.11::el7 |
before 0:3.11.82-1.git.0.efb6af0.el7 | 0:3.11.82-1.git.0.efb6af0.el7 |
Show 44 moreShow less
| Package | Affected | Fixed |
|---|---|---|
atomic-openshift-deschedulerRed Hat:openshift:3.11::el7 |
before 0:3.11.82-1.git.300.89765c9.el7 | 0:3.11.82-1.git.300.89765c9.el7 |
atomic-openshift-docker-excluderRed Hat:openshift:3.11::el7 |
before 0:3.11.82-1.git.0.08bc31b.el7 | 0:3.11.82-1.git.0.08bc31b.el7 |
atomic-openshift-dockerregistryRed Hat:openshift:3.11::el7 |
before 0:3.11.82-1.git.452.0ce6383.el7 | 0:3.11.82-1.git.452.0ce6383.el7 |
atomic-openshift-excluderRed Hat:openshift:3.11::el7 |
before 0:3.11.82-1.git.0.08bc31b.el7 | 0:3.11.82-1.git.0.08bc31b.el7 |
atomic-openshift-hyperkubeRed Hat:openshift:3.11::el7 |
before 0:3.11.82-1.git.0.08bc31b.el7 | 0:3.11.82-1.git.0.08bc31b.el7 |
atomic-openshift-hypershiftRed Hat:openshift:3.11::el7 |
before 0:3.11.82-1.git.0.08bc31b.el7 | 0:3.11.82-1.git.0.08bc31b.el7 |
atomic-openshift-masterRed Hat:openshift:3.11::el7 |
before 0:3.11.82-1.git.0.08bc31b.el7 | 0:3.11.82-1.git.0.08bc31b.el7 |
atomic-openshift-metrics-serverRed Hat:openshift:3.11::el7 |
before 0:3.11.82-1.git.52.2fdca3f.el7 | 0:3.11.82-1.git.52.2fdca3f.el7 |
atomic-openshift-nodeRed Hat:openshift:3.11::el7 |
before 0:3.11.82-1.git.0.08bc31b.el7 | 0:3.11.82-1.git.0.08bc31b.el7 |
atomic-openshift-node-problem-detectorRed Hat:openshift:3.11::el7 |
before 0:3.11.82-1.git.254.a448936.el7 | 0:3.11.82-1.git.254.a448936.el7 |
atomic-openshift-podRed Hat:openshift:3.11::el7 |
before 0:3.11.82-1.git.0.08bc31b.el7 | 0:3.11.82-1.git.0.08bc31b.el7 |
atomic-openshift-sdn-ovsRed Hat:openshift:3.11::el7 |
before 0:3.11.82-1.git.0.08bc31b.el7 | 0:3.11.82-1.git.0.08bc31b.el7 |
atomic-openshift-service-idlerRed Hat:openshift:3.11::el7 |
before 0:3.11.82-1.git.14.e353758.el7 | 0:3.11.82-1.git.14.e353758.el7 |
atomic-openshift-template-service-brokerRed Hat:openshift:3.11::el7 |
before 0:3.11.82-1.git.0.08bc31b.el7 | 0:3.11.82-1.git.0.08bc31b.el7 |
atomic-openshift-testsRed Hat:openshift:3.11::el7 |
before 0:3.11.82-1.git.0.08bc31b.el7 | 0:3.11.82-1.git.0.08bc31b.el7 |
atomic-openshift-web-consoleRed Hat:openshift:3.11::el7 |
before 0:3.11.82-1.git.355.5e8b1d9.el7 | 0:3.11.82-1.git.355.5e8b1d9.el7 |
golang-github-openshift-oauth-proxyRed Hat:openshift:3.11::el7 |
before 0:3.11.82-1.git.425.7cac034.el7 | 0:3.11.82-1.git.425.7cac034.el7 |
golang-github-prometheus-alertmanagerRed Hat:openshift:3.11::el7 |
before 0:3.11.82-1.git.0.3bf41ce.el7 | 0:3.11.82-1.git.0.3bf41ce.el7 |
golang-github-prometheus-node_exporterRed Hat:openshift:3.11::el7 |
before 0:3.11.82-1.git.1063.48444e8.el7 | 0:3.11.82-1.git.1063.48444e8.el7 |
golang-github-prometheus-prometheusRed Hat:openshift:3.11::el7 |
before 0:3.11.82-1.git.5027.9d24833.el7 | 0:3.11.82-1.git.5027.9d24833.el7 |
haproxyRed Hat:openshift:3.11::el7 |
before 0:1.8.17-3.el7 | 0:1.8.17-3.el7 |
haproxy-debuginfoRed Hat:openshift:3.11::el7 |
before 0:1.8.17-3.el7 | 0:1.8.17-3.el7 |
haproxy18Red Hat:openshift:3.11::el7 |
before 0:1.8.17-3.el7 | 0:1.8.17-3.el7 |
jenkinsRed Hat:openshift:3.11::el7 |
before 0:2.150.2.1549032159-1.el7 | 0:2.150.2.1549032159-1.el7 |
jenkins-2-pluginsRed Hat:openshift:3.11::el7 |
before 0:3.11.1549642489-1.el7 | 0:3.11.1549642489-1.el7 |
openshift-ansibleRed Hat:openshift:3.11::el7 |
before 0:3.11.82-3.git.0.9718d0a.el7 | 0:3.11.82-3.git.0.9718d0a.el7 |
openshift-ansible-docsRed Hat:openshift:3.11::el7 |
before 0:3.11.82-3.git.0.9718d0a.el7 | 0:3.11.82-3.git.0.9718d0a.el7 |
openshift-ansible-playbooksRed Hat:openshift:3.11::el7 |
before 0:3.11.82-3.git.0.9718d0a.el7 | 0:3.11.82-3.git.0.9718d0a.el7 |
openshift-ansible-rolesRed Hat:openshift:3.11::el7 |
before 0:3.11.82-3.git.0.9718d0a.el7 | 0:3.11.82-3.git.0.9718d0a.el7 |
openshift-ansible-testRed Hat:openshift:3.11::el7 |
before 0:3.11.82-3.git.0.9718d0a.el7 | 0:3.11.82-3.git.0.9718d0a.el7 |
openshift-enterprise-autohealRed Hat:openshift:3.11::el7 |
before 0:3.11.82-1.git.219.0b5aff4.el7 | 0:3.11.82-1.git.219.0b5aff4.el7 |
openshift-enterprise-cluster-capacityRed Hat:openshift:3.11::el7 |
before 0:3.11.82-1.git.380.cf11c51.el7 | 0:3.11.82-1.git.380.cf11c51.el7 |
prometheusRed Hat:openshift:3.11::el7 |
before 0:3.11.82-1.git.5027.9d24833.el7 | 0:3.11.82-1.git.5027.9d24833.el7 |
prometheus-alertmanagerRed Hat:openshift:3.11::el7 |
before 0:3.11.82-1.git.0.3bf41ce.el7 | 0:3.11.82-1.git.0.3bf41ce.el7 |
prometheus-node-exporterRed Hat:openshift:3.11::el7 |
before 0:3.11.82-1.git.1063.48444e8.el7 | 0:3.11.82-1.git.1063.48444e8.el7 |
haproxyRed Hat:openshift:3.9::el7 |
before 0:1.8.17-3.el7 | 0:1.8.17-3.el7 |
haproxy-debuginfoRed Hat:openshift:3.9::el7 |
before 0:1.8.17-3.el7 | 0:1.8.17-3.el7 |
haproxy18Red Hat:openshift:3.9::el7 |
before 0:1.8.17-3.el7 | 0:1.8.17-3.el7 |
rh-haproxy18-haproxyRed Hat:rhel_software_collections:3::el7 |
before 0:1.8.17-1.el7 | 0:1.8.17-1.el7 |
rh-haproxy18-haproxy-debuginfoRed Hat:rhel_software_collections:3::el7 |
before 0:1.8.17-1.el7 | 0:1.8.17-1.el7 |
rh-haproxy18-haproxy-syspathsRed Hat:rhel_software_collections:3::el7 |
before 0:1.8.17-1.el7 | 0:1.8.17-1.el7 |
haproxySUSE:Linux Enterprise High Availability Extension 15 |
before 1.8.15~git0.6b6a350a-3.6.2 | 1.8.15~git0.6b6a350a-3.6.2 |
haproxyUbuntu:16.04:LTS |
before 1.6.3-1ubuntu0.2, plus listed versions 1.5.14-11.5.15-11.6.2-11.6.2-21.6.2-2ubuntu11.6.2-2ubuntu31.6.3-11.6.3-1ubuntu0.1 |
1.6.3-1ubuntu0.2 |
haproxyUbuntu:18.04:LTS |
before 1.8.8-1ubuntu0.3, plus listed versions 1.7.9-1ubuntu11.7.9-1ubuntu21.8.4-11.8.7-11.8.8-11.8.8-1ubuntu0.11.8.8-1ubuntu0.2 |
1.8.8-1ubuntu0.3 |
History
| Recorded | Changed | Sources |
|---|---|---|
| aliases | EUVD | |
| first indexed | CVE List, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2018-20102 is a high vulnerability (CVSS 7.5) in Haproxy, published December 12, 2018. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 4.15%, the 90th percentile. Fixed in haproxy 1.8.15-1.
References
git.haproxy.org?p=haproxy.git%3Ba=commit%3Bh=efbbdf72992cd20458259962346044cafd9331c0
usn.ubuntu.com/3858-1
access.redhat.com/errata/RHBA-2019:0326
securityfocus.com/bid/106223
Show 127 moreShow less
lists.debian.org/debian-lts-announce/2022/05/msg00045.html
nvd.nist.gov/vuln/detail/CVE-2018-20102
github.com/advisories/GHSA-5m22-hqfx-435p
security-tracker.debian.org/tracker/CVE-2018-20102
bugzilla.redhat.com/show_bug.cgi?id=1506736
security.access.redhat.com/data/csaf/v2/advisories/2019/rhba-2019_0326.json
cve.org/CVERecord?id=CVE-2018-20102
mail-archive.com/[email protected]/msg32055.html
jenkins.io/security/advisory/2019-01-08
suse.com/support/update/announcement/2019/suse-su-20190061-1
bugzilla.suse.com/1119368
ubuntu.com/security/CVE-2018-20102
lists.opensuse.org/archives/list/[email protected]/thread/TZXJ2LKYAOHD67OUI6IBBWM5LXXB753E