DNS cache poisoning via unchecked CNAME bailiwick
Published Jun 12, 2026 · Updated Jun 12, 2026
DNS cache poisoning in Netty 4.1.134.Final and earlier and 4.2.0.Final through 4.2.14.Final allows remote attackers to redirect DNS lookups. DnsResolveContext.buildAliasMap blindly caches every CNAME in a response's ANSWER section without confirming that its name belongs to the queried domain. Exploitation requires a crafted DNS answer to reach an application using the resolver; a poisoned alias can redirect subsequent connections and expose or alter application data.
Summary
What happened
DNS cache poisoning in Netty 4.1.134.Final and earlier and 4.2.0.Final through 4.2.14.Final allows remote attackers to redirect DNS lookups. DnsResolveContext.buildAliasMap blindly caches every CNAME in a response's ANSWER section without confirming that its name belongs to the queried domain. Exploitation requires a crafted DNS answer to reach an application using the resolver; a poisoned alias can redirect subsequent connections and expose or alter application data.
The record
- CVE
- CVE-2026-45674
- Published
- Jun 12, 2026
- Updated
- Jun 12, 2026
- Vendor
- The Netty Project
- Product
- Netty
- Classifications
- CWE-346, CWE-345, T1557
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Jun 12, 2026CVE publishedPublication date reported by the CVE source.
- Jun 12, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=< 4.1.135.Final
- Affected versionversion=>= 4.2.0.Final, < 4.2.15.Final
What conditions does exploitation require?
What is affected?
Published CVSS scores
CVSS describes severity. EPSS estimates exploitation probability.
Attacks
What attackers are doing with it
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Weakness, pattern, technique
Public exploit references
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Technologies
Your stack
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Your stack
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