CoreDNS Loop Detection Denial of Service Vulnerability
Summary
| CVE | CVE-2026-26018 |
|---|---|
| State | PUBLISHED |
| Assigner | GitHub_M |
| Source Priority | CVE Program / NVD first with legacy fallback |
| Published | 2026-03-06 16:16:10 UTC |
| Updated | 2026-07-15 02:18:59 UTC |
| Description | CoreDNS is a DNS server that chains plugins. Prior to version 1.14.2, a denial of service vulnerability exists in CoreDNS's loop detection plugin that allows an attacker to crash the DNS server by sending specially crafted DNS queries. The vulnerability stems from the use of a predictable pseudo-random number generator (PRNG) for generating a secret query name, combined with a fatal error handler that terminates the entire process. This issue has been patched in version 1.14.2. |
Risk And Classification
Primary CVSS: v3.1 7.5 HIGH from ADP
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
EPSS: 0.010930000 probability, percentile 0.616900000 (date 2026-07-16)
Problem Types: CWE-337 | CWE-400 | CWE-770 | CWE-1241 | CWE-337 CWE-337: Predictable Seed in Pseudo-Random Number Generator (PRNG) | CWE-770 CWE-770: Allocation of Resources Without Limits or Throttling | CWE-400 CWE-400: Uncontrolled Resource Consumption | CWE-1241 Use of Predictable Algorithm in Random Number Generator
| Version | Source | Type | Score | Severity | Vector |
|---|---|---|---|---|---|
| 3.1 | ADP | CVSS | 7.5 | HIGH | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
| 3.1 | [email protected] | Secondary | 7.5 | HIGH | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
| 3.1 | 0b0ca135-0b70-47e7-9f44-1890c2a1c46c | Secondary | 7.5 | HIGH | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
| 3.1 | CNA | DECLARED | 7.5 | HIGH | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
CVSS v3.1 Breakdown
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
NVD Known Affected Configurations (CPE 2.3)
| Type | Vendor | Product | Version | Update | Edition | Language |
|---|---|---|---|---|---|---|
| Application | Coredns.io | Coredns | All | All | All | All |
Vendor Declared Affected Products
| Source | Vendor | Product | Version | Platforms |
|---|---|---|---|---|
| CNA | Coredns | Coredns | affected < 1.14.2 | Not specified |
| ADP | Red Hat | Red Hat Advanced Cluster Management For Kubernetes 2.13 | unaffected 1782924920 * rpm | Not specified |
| ADP | Red Hat | Red Hat Advanced Cluster Management For Kubernetes 2.13 | unaffected 1782924937 * rpm | Not specified |
| ADP | Red Hat | Red Hat Advanced Cluster Management For Kubernetes 2.14 | unaffected 1780204232 * rpm | Not specified |
| ADP | Red Hat | Red Hat Advanced Cluster Management For Kubernetes 2.14 | unaffected 1780204249 * rpm | Not specified |
| ADP | Red Hat | Red Hat Advanced Cluster Management For Kubernetes 2.15 | unaffected 1774086225 * rpm | Not specified |
| ADP | Red Hat | Red Hat Connectivity Link 1 | Not specified | Not specified |
| ADP | Red Hat | Red Hat OpenShift Container Platform 4 | Not specified | Not specified |
References
| Reference | Source | Link | Tags |
|---|---|---|---|
| security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-26018.json | 0b0ca135-0b70-47e7-9f44-1890c2a1c46c | security.access.redhat.com | |
| github.com/coredns/coredns/releases/tag/v1.14.2 | [email protected] | github.com | Product, Release Notes |
| bugzilla.redhat.com/show_bug.cgi | 0b0ca135-0b70-47e7-9f44-1890c2a1c46c | bugzilla.redhat.com | |
| access.redhat.com/errata/RHSA-2026:25127 | 0b0ca135-0b70-47e7-9f44-1890c2a1c46c | access.redhat.com | |
| github.com/coredns/coredns/security/advisories/GHSA-h75p-j8xm-m278 | [email protected] | github.com | Exploit, Vendor Advisory |
| access.redhat.com/security/cve/CVE-2026-26018 | 0b0ca135-0b70-47e7-9f44-1890c2a1c46c | access.redhat.com | |
| access.redhat.com/errata/RHSA-2026:36873 | 0b0ca135-0b70-47e7-9f44-1890c2a1c46c | access.redhat.com | |
| access.redhat.com/errata/RHSA-2026:8151 | 0b0ca135-0b70-47e7-9f44-1890c2a1c46c | access.redhat.com | |
| CVE Program record | CVE.ORG | www.cve.org | canonical |
| NVD vulnerability detail | NVD | nvd.nist.gov | canonical, analysis |
Additional Advisory Data
| Source | Time | Event |
|---|---|---|
| ADP | 2026-03-06T16:01:38.150Z | Reported to Red Hat. |
| ADP | 2026-03-06T15:35:50.801Z | Made public. |
Solutions
ADP: RHSA-2026:36873: Red Hat Advanced Cluster Management for Kubernetes 2.13
ADP: RHSA-2026:25127: Red Hat Advanced Cluster Management for Kubernetes 2.14
ADP: RHSA-2026:8151: Red Hat Advanced Cluster Management for Kubernetes 2.15
Workarounds
ADP: Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.