CVE-2026-45673

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

MEDIUM

6.8

CVSS Score

Published: June 12, 2026 at 02:16 PM UTC

Updated: June 17, 2026 at 10:52 AM UTC

1 product affected across 1 vendorNetty

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Severity

MEDIUM6.8

Exploit prediction

EPSS 0.3%

SSVC

No known exploit

Description

Netty is a network application framework for development of protocol servers and clients. Prior to versions 4.1.135.Final and 4.2.15.Final, 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). Versions 4.1.135.Final and 4.2.15.Final patch the issue.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

Netty · Nettymaven

95%

v < 4.1.135v < 4.1.135.Finalv < 4.2.15.Final4.2.0 ≤ v < 4.2.15

Affected range stops below 4.1.135, so it looks safe — our inference, not a vendor statement

Affected range stops below 4.1.135.Final, so it looks safe — our inference, not a vendor statement

Affected range stops below 4.2.15, so it looks safe — our inference, not a vendor statement

Affected range stops below 4.2.15.Final, so it looks safe — our inference, not a vendor statement

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

Patch and advisory references

https://github.com/netty/netty/security/advisories/GHSA-xmv7-r254-6q78

References (3)

x_refsource_CONFIRMVendor Advisory

Source: cverecord

https://github.com/netty/netty/security/advisories/GHSA-xmv7-r254-6q78

x_refsource_MISCRelease Notes

Source: cverecord

https://github.com/netty/netty/releases/tag/netty-4.1.135.Final

x_refsource_MISCRelease Notes

Source: cverecord

https://github.com/netty/netty/releases/tag/netty-4.2.15.Final

SSVC — Action Prioritization

SSVCNo known exploitNot automatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

6.8MEDIUMGitHub_M

Attack Vector: NETWORK
Complexity: HIGH
Privileges: NONE
User Interaction: NONE
Scope: CHANGED
Confidentiality: NONE
Integrity: HIGH
Availability: NONE

Vector?

Quick Info

StatusANALYZED

CWE

CWE-330CWE-340

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