CVE-2025-29908 | Netty QUIC hash collision DoS attack

Netty QUIC codec is a QUIC codec for netty which makes use of quiche. An issue was discovered in the codec. A hash collision vulnerability (in the hash map used to manage connections) allows remote attackers to cause a considerable CPU load on the server (a Hash DoS attack) by initiating connections with colliding Source Connection IDs (SCIDs). This vulnerability is fixed in 0.0.71.Final.

Published: 2025-03-31 Last update: 2026-04-15 Assigner: [email protected] Source: [email protected]

Conclusion & alert: CVE-2025-29908 is rated Moderate Risk (43.3/100): CVSS Medium severity, with medium exploitation likelihood (EPSS 0.44%). Mandatory action: Review affected assets and schedule remediation.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2025-29908

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-05-06 0.49% 0.44% -0.05%
2 2026-01-25 0.11% 0.49% +0.38%
3 2025-11-21 0.11%

Full EPSS history (5 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2025-29908

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
5.3 3.1 MEDIUM
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:L)
Might cause slowdowns, glitches, or partial disruption—not a full brick.
3.9 1.4 [email protected]

Weakness enumeration for CVE-2025-29908

GitHub Security Advisory for CVE-2025-29908

GHSA-hqqc-jr88-p6x2 · Severity: medium · Ecosystem: maven — Netty QUIC hash collision DoS attack

Affected software / configurations for CVE-2025-29908

Vendor Product Version Raw CPE
No affected products in dataset.

References for CVE-2025-29908

cvelogic Threat Intelligence