CVE-2025-29908Network attack vector

Server stall via colliding source connection IDs

Published Mar 31, 2025 · Updated Apr 1, 2025

Hash-collision denial of service in Netty Incubator Codec QUIC before 0.0.71.Final allows remote attackers to stall servers. The QuicheQuicCodec connectionIdToChannel map hashes attacker-chosen SCIDs without a collision-resistant keyed hash, making connection inserts and lookups consume excessive CPU. Unauthenticated QUIC connection attempts are sufficient; the documented consequence is a server stall from CPU exhaustion, not data access or modification.

CVSS severity5.3
Medium
EPSS probability0.57%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Hash-collision denial of service in Netty Incubator Codec QUIC before 0.0.71.Final allows remote attackers to stall servers. The QuicheQuicCodec connectionIdToChannel map hashes attacker-chosen SCIDs without a collision-resistant keyed hash, making connection inserts and lookups consume excessive CPU. Unauthenticated QUIC connection attempts are sufficient; the documented consequence is a server stall from CPU exhaustion, not data access or modification.

The record

CVE
CVE-2025-29908
Published
Mar 31, 2025
Updated
Apr 1, 2025
Vendor
The Netty Project
Product
Netty Incubator Codec QUIC
Classifications
CWE-407, T1499.002
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Mar 31, 2025CVE publishedPublication date reported by the CVE source.
  2. Apr 1, 2025Record 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.

  1. Affected versionversion=< 0.0.71.Final

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

The Netty Project · Netty Incubator Codec QUICversion=< 0.0.71.Final

Published CVSS scores

5.3GitHub, Inc.CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-407Inefficient Algorithmic Complexity
T1499.002Service Exhaustion Flood

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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