Update dependency io.netty:netty-resolver-dns to v4.1.135.Final [SECURITY] (main)

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This PR contains the following updates:

Package	Change	Age	Adoption	Passing	Confidence
io.netty:netty-resolver-dns (source)	4.1.118.Final → 4.1.135.Final

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Warning

Some dependencies could not be looked up. Check the warning logs for more information.

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Netty: DNS Cache Poisoning due to Predictable PRNG and Default Static Source Port

CVE-2026-45673 / GHSA-xmv7-r254-6q78

More information

Details

Summary

Netty's DNS resolver uses a predictable PRNG for generating DNS transaction IDs and defaults to a static UDP source port. This combination reduces the entropy of DNS queries, enabling DNS Cache Poisoning (Kaminsky attack).

Details

Two factors contribute to this vulnerability in io.netty.resolver.dns:

• Predictable Query IDs: DnsQueryIdSpace manages 16-bit transaction IDs in buckets of 16,384 IDs. It initializes only the first bucket. When an ID is returned, it is pushed back into the bucket at a random index generated by java.util.concurrent.ThreadLocalRandom:

Random random = ThreadLocalRandom.current();
int insertionPosition = random.nextInt(count + 1);

Because ThreadLocalRandom is a predictable LCG and the resolver operates within a single bucket, the sequence of IDs is predictable once the PRNG state is mathematically recovered.

• Default Static Source Port: DnsNameResolverBuilder defaults to a channelStrategy of ChannelPerResolver. This binds the DatagramChannel once, resulting in a static source port for all subsequent queries.

Combined, a static source port and predictable transaction IDs reduces the entropy required to secure DNS resolution against spoofing.

Impact

DNS Cache Poisoning. Downstream applications using the default Netty DNS resolver may connect to malicious IPs, leading to traffic interception or MitM attacks.

Severity

• CVSS Score: 6.8 / 10 (Medium)
• Vector String: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:N/I:H/A:N

References

• https://github.com/netty/netty/security/advisories/GHSA-xmv7-r254-6q78
• https://github.com/netty/netty/releases/tag/netty-4.1.135.Final
• https://github.com/netty/netty/releases/tag/netty-4.2.15.Final
• https://nvd.nist.gov/vuln/detail/CVE-2026-45673
• https://github.com/advisories/GHSA-xmv7-r254-6q78

This data is provided by the GitHub Advisory Database (CC-BY 4.0).

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Netty Vulnerable to DNS Cache Poisoning via Missing Bailiwick Checks in CNAME Records

CVE-2026-45674 / GHSA-676x-f7gg-47vc

More information

Details

Summary

Netty's DnsResolveContext fails to validate the origin (bailiwick) of CNAME records in DNS responses.

Details

In io.netty.resolver.dns.DnsResolveContext#buildAliasMap, the resolver processes the ANSWER section of a DNS response and blindly caches all CNAME records it finds.

According to https://datatracker.ietf.org/doc/html/rfc5452#section-6

Care must be taken to only accept
   data if it is known that the originator is authoritative for the
   QNAME or a parent of the QNAME.
   One very simple way to achieve this is to only accept data if it is
   part of the domain for which the query was intended.

Impact

DNS Cache Poisoning (Bailiwick Bypass). Any application using Netty's DNS resolver is impacted.

Severity

• CVSS Score: 8.7 / 10 (High)
• Vector String: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:N

References

• https://github.com/netty/netty/security/advisories/GHSA-676x-f7gg-47vc
• https://github.com/netty/netty/releases/tag/netty-4.1.135.Final
• https://github.com/netty/netty/releases/tag/netty-4.2.15.Final
• https://nvd.nist.gov/vuln/detail/CVE-2026-45674
• https://github.com/advisories/GHSA-676x-f7gg-47vc

This data is provided by the GitHub Advisory Database (CC-BY 4.0).

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Netty has Insufficient Bailiwick Validation for NS Records

CVE-2026-47691 / GHSA-5pvg-856g-cp85

More information

Details

Summary

Netty's DnsResolveContext insufficiently validates the bailiwick of NS records, enabling DNS Cache Poisoning. An attacker controlling an authoritative name server for a subdomain can poison the cache for parent domains (like .co.uk).

Details

In io.netty.resolver.dns.DnsResolveContext.AuthoritativeNameServerList#add method accepts any NS record from the AUTHORITY section as long as the record's name is a suffix of the questionName.

This means if the resolver queries evil.co.uk., it will accept an NS record claiming authority over co.uk.. Subsequently, the handleWithAdditional method caches the associated A records from the ADDITIONAL section directly into the authoritativeDnsServerCache under the parent domain's key (co.uk.). This bypasses standard bailiwick rules, where a server authoritative for a subdomain should not be trusted to provide authoritative records for its parent. The poisoned cache is then used for all future resolutions under co.uk..

The io.netty.resolver.dns.DnsResolveContext.AuthoritativeNameServerList#cache method only prevents caching if the record is for the root zone (dots == 1).

Impact

DNS Cache Poisoning. Any application using Netty's DNS resolver is impacted.

Severity

• CVSS Score: 8.7 / 10 (High)
• Vector String: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:N

References

• https://github.com/netty/netty/security/advisories/GHSA-5pvg-856g-cp85
• https://github.com/netty/netty/releases/tag/netty-4.1.135.Final
• https://github.com/netty/netty/releases/tag/netty-4.2.15.Final
• https://nvd.nist.gov/vuln/detail/CVE-2026-47691
• https://github.com/advisories/GHSA-5pvg-856g-cp85

This data is provided by the GitHub Advisory Database (CC-BY 4.0).

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Netty has Insufficient Bailiwick Validation for NS Records

CVE-2026-47691 / GHSA-5pvg-856g-cp85

More information

Details

Summary

Netty's DnsResolveContext insufficiently validates the bailiwick of NS records, enabling DNS Cache Poisoning. An attacker controlling an authoritative name server for a subdomain can poison the cache for parent domains (like .co.uk).

Details

In io.netty.resolver.dns.DnsResolveContext.AuthoritativeNameServerList#add method accepts any NS record from the AUTHORITY section as long as the record's name is a suffix of the questionName.

This means if the resolver queries evil.co.uk., it will accept an NS record claiming authority over co.uk.. Subsequently, the handleWithAdditional method caches the associated A records from the ADDITIONAL section directly into the authoritativeDnsServerCache under the parent domain's key (co.uk.). This bypasses standard bailiwick rules, where a server authoritative for a subdomain should not be trusted to provide authoritative records for its parent. The poisoned cache is then used for all future resolutions under co.uk..

The io.netty.resolver.dns.DnsResolveContext.AuthoritativeNameServerList#cache method only prevents caching if the record is for the root zone (dots == 1).

Impact

DNS Cache Poisoning. Any application using Netty's DNS resolver is impacted.

Severity

• CVSS Score: 8.7 / 10 (High)
• Vector String: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:N

References

• https://github.com/netty/netty/security/advisories/GHSA-5pvg-856g-cp85
• https://nvd.nist.gov/vuln/detail/CVE-2026-47691
• https://github.com/netty/netty
• https://github.com/netty/netty/releases/tag/netty-4.1.135.Final
• https://github.com/netty/netty/releases/tag/netty-4.2.15.Final

This data is provided by OSV and the GitHub Advisory Database (CC-BY 4.0).

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Netty Vulnerable to DNS Cache Poisoning via Missing Bailiwick Checks in CNAME Records

CVE-2026-45674 / GHSA-676x-f7gg-47vc

More information

Details

Summary

Netty's DnsResolveContext fails to validate the origin (bailiwick) of CNAME records in DNS responses.

Details

In io.netty.resolver.dns.DnsResolveContext#buildAliasMap, the resolver processes the ANSWER section of a DNS response and blindly caches all CNAME records it finds.

According to https://datatracker.ietf.org/doc/html/rfc5452#section-6

Care must be taken to only accept
   data if it is known that the originator is authoritative for the
   QNAME or a parent of the QNAME.
   One very simple way to achieve this is to only accept data if it is
   part of the domain for which the query was intended.

Impact

DNS Cache Poisoning (Bailiwick Bypass). Any application using Netty's DNS resolver is impacted.

Severity

• CVSS Score: 8.7 / 10 (High)
• Vector String: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:N

References

• https://github.com/netty/netty/security/advisories/GHSA-676x-f7gg-47vc
• https://nvd.nist.gov/vuln/detail/CVE-2026-45674
• https://github.com/netty/netty
• https://github.com/netty/netty/releases/tag/netty-4.1.135.Final
• https://github.com/netty/netty/releases/tag/netty-4.2.15.Final

This data is provided by OSV and the GitHub Advisory Database (CC-BY 4.0).

---

Netty: DNS Cache Poisoning due to Predictable PRNG and Default Static Source Port

CVE-2026-45673 / GHSA-xmv7-r254-6q78

More information

Details

Summary

Netty's DNS resolver uses a predictable PRNG for generating DNS transaction IDs and defaults to a static UDP source port. This combination reduces the entropy of DNS queries, enabling DNS Cache Poisoning (Kaminsky attack).

Details

Two factors contribute to this vulnerability in io.netty.resolver.dns:

• Predictable Query IDs: DnsQueryIdSpace manages 16-bit transaction IDs in buckets of 16,384 IDs. It initializes only the first bucket. When an ID is returned, it is pushed back into the bucket at a random index generated by java.util.concurrent.ThreadLocalRandom:

Random random = ThreadLocalRandom.current();
int insertionPosition = random.nextInt(count + 1);

Because ThreadLocalRandom is a predictable LCG and the resolver operates within a single bucket, the sequence of IDs is predictable once the PRNG state is mathematically recovered.

• Default Static Source Port: DnsNameResolverBuilder defaults to a channelStrategy of ChannelPerResolver. This binds the DatagramChannel once, resulting in a static source port for all subsequent queries.

Combined, a static source port and predictable transaction IDs reduces the entropy required to secure DNS resolution against spoofing.

Impact

DNS Cache Poisoning. Downstream applications using the default Netty DNS resolver may connect to malicious IPs, leading to traffic interception or MitM attacks.

Severity

• CVSS Score: 6.8 / 10 (Medium)
• Vector String: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:N/I:H/A:N

References

• https://github.com/netty/netty/security/advisories/GHSA-xmv7-r254-6q78
• https://nvd.nist.gov/vuln/detail/CVE-2026-45673
• https://github.com/netty/netty
• https://github.com/netty/netty/releases/tag/netty-4.1.135.Final
• https://github.com/netty/netty/releases/tag/netty-4.2.15.Final

This data is provided by OSV and the GitHub Advisory Database (CC-BY 4.0).

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