CVE-2023-34054 | Reactor Netty HTTP Server Metrics DoS Vulnerability

In Reactor Netty HTTP Server, versions 1.1.x prior to 1.1.13 and versions 1.0.x prior to 1.0.39, it is possible for a user to provide specially crafted HTTP requests that may cause a denial-of-service (DoS) condition. Specifically, an application is vulnerable if Reactor Netty HTTP Server built-in integration with Micrometer is enabled.

Published: 2023-11-28 Last update: 2024-11-21 Assigner: [email protected] Source: [email protected]

Conclusion & alert: CVE-2023-34054 is rated Moderate Risk (41.2/100): CVSS Medium severity, with medium exploitation likelihood (EPSS 0.91%). 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-2023-34054

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 2026-06-15 0.17% 0.91% +0.74%
2 2025-11-21 0.65% 0.17% -0.48%
3 2025-11-18 0.65%

Full EPSS history (10 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2023-34054

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]
7.5 3.1 HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H 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:H)
Could take the service down hard or make it unusable for people who depend on it.
3.9 3.6 [email protected]

Weakness enumeration for CVE-2023-34054

GitHub Security Advisory for CVE-2023-34054

GHSA-q24v-hpg3-v3jp · Severity: high · Ecosystem: maven — Reactor Netty HTTP Server denial of service vulnerability

Affected software / configurations for CVE-2023-34054

Vendor Product Version Raw CPE
pivotal reactor_netty < 1.0.39 cpe:2.3:a:pivotal:reactor_netty:*:*:*:*:*:*:*:*
pivotal reactor_netty >= 1.1.0, < 1.1.13 cpe:2.3:a:pivotal:reactor_netty:*:*:*:*:*:*:*:*

References for CVE-2023-34054

cvelogic Threat Intelligence