dbcve.org
CorednsApplication · Coredns.io

CVE-2023-28452

HIGH · 7.5 CVSS v3.1 Published 2024-09-18
Fix available
A fix is available. Upgrade to after 1.10.1 or later.
See remediation →
84/100
Remediation priority · High
Remotely reachable No privileges Zero-click

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
An issue was discovered in CoreDNS through 1.10.1. There is a vulnerability in DNS resolving software, which triggers a resolver to ignore valid responses, thus causing denial of service for normal resolution. In an exploit, the attacker could just forge a response targeting the source port of a vulnerable resolver without the need to guess the correct TXID.

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis · high confidence

CVE-2023-28452 is a DNS resolver vulnerability in CoreDNS through 1.10.1 that allows an attacker to cause denial of service by forging DNS responses targeting the source port of a vulnerable resolver, without needing to guess the TXID. The flaw causes the resolver to ignore valid responses, disrupting normal DNS resolution for legitimate users.

MitigationUpgrade CoreDNS to a version beyond 1.10.1 that includes the fix for this source port handling vulnerability, or apply any available security patches.

Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.

Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.

NVD · CPE data
CorednsApplication
Affected:<= 1.10.1

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
High

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.

dbcve checks

Work through these to decide whether this CVE applies to you.

  1. Confirm CoreDNS is installed and running
    Run 'coredns --version' or check running processes with 'ps aux | grep coredns'
    Affected if CoreDNS is running with version 1.10.1 or lower
  2. Verify the exact CoreDNS version
    Execute 'coredns --version' and note the version number in the output
    Affected if Version is 1.10.1 or any version lower than 1.10.1
  3. Identify if CoreDNS is configured as a DNS resolver
    Examine the Corefile configuration (typically at /etc/coredns/Corefile or /etc/Corefile) and look for 'forward' directives or proxy configuration that routes DNS queries to upstream resolvers
    Affected if The forward or proxy directive is present and pointing to upstream DNS servers, indicating resolver functionality
  4. Check if DNS port is exposed and accessible
    Verify that port 53 (DNS) is listening on the CoreDNS server using 'netstat -tulpn | grep :53' or 'ss -tulpn | grep :53'
    Affected if Port 53 is open and serving DNS queries, making the vulnerable source port handling exploitable

You are affected if CoreDNS version 1.10.1 or lower is running as a DNS resolver with forwarding enabled and serving DNS queries on port 53.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

dbcve · scoped
Upgrade available Upgrade to a release after 1.10.1
Interim mitigation

Upgrade CoreDNS to a version beyond 1.10.1 that includes the fix for this source port handling vulnerability, or apply any available security patches.

Recommended fix High confidence

CoreDNS 1.11.0 or later (e.g., 1.11.1, 1.12.0)

  1. 1. Identify all CoreDNS instances running version 1.10.1 or earlier in your infrastructure
  2. 2. Plan an upgrade window ensuring minimal service disruption
  3. 3. Backup current CoreDNS configuration files (typically located in /etc/coredns/ or as ConfigMaps in Kubernetes)
  4. 4. For containerized deployments: update the image tag to coredns/coredns:1.11.0 or later
  5. 5. For binary installations: download the updated binary from the official CoreDNS releases page
  6. 6. Apply the configuration backup to the upgraded instance
  7. 7. Verify the upgrade was successful by checking the CoreDNS version (coredns -version)
  8. 8. Test DNS resolution functionality to confirm normal operation
Caveat Review release notes for any plugin behavior changes or deprecations between 1.10.x and 1.11.x; ensure any custom plugins remain compatible

Generated from the published advisory — verify against the referenced sources before acting.

Fix this in Coredns Scoped from the published advisory
  • Consultation1.0 h
  • Implementation2.0 h
  • Testing2.0 h
  • Review / QA1.0 h
6.0 hours of engineering $1,040
Get the upgrade done

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $1,664.

Scan for this in your stack

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References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2023-28452 in production — separate from our analysis above.

No notes yet

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What this is

A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.

What belongs here
  • Verified mitigations, workarounds, and config changes
  • Version or environment caveats, and links to real fixes
  • No weaponised exploit code, or anything meant to cause harm
  • No spam, self-promotion, credentials, or personal data