CVE-2026-49361 | Apache Fluss Netty Frame Decoder Memory Exhaustion Vulnerability

Apache Fluss versions prior to 0.9.1 configure the Netty LengthFieldBasedFrameDecoder with Integer.MAX_VALUE as the maximum frame length, allowing unauthenticated remote attackers to exhaust JVM heap memory on TabletServer and CoordinatorServer by sending specially crafted frame headers, resulting in denial of service. This issue affects Apache Fluss (incubating): 0.8.0 and 0.9.0. Users are recommended to upgrade to version 0.9.1, which fixes the issue.

Published: 2026-06-01 Last update: 2026-06-01 Assigner: [email protected] Source: [email protected]

Conclusion & alert: CVE-2026-49361 is rated Moderate Risk (42.6/100): CVSS High severity, with low exploitation likelihood (EPSS 0.15%). 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-2026-49361

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 2026-06-02 0.05% 0.15% +0.10%
2 2026-06-01 0.05%

Full EPSS history (2 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2026-49361

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
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 134c704f-9b21-4f2e-91b3-4a467353bcc0

Weakness enumeration for CVE-2026-49361

GitHub Security Advisory for CVE-2026-49361

GHSA-4c39-fwgj-4vq7 · Severity: high — Apache Fluss versions prior to 0.9.1 configure the Netty LengthFieldBasedFrameDecoder with...

Affected software / configurations for CVE-2026-49361

Vendor Product Version Raw CPE
apache fluss >= 0.8.0, < 0.9.1 cpe:2.3:a:apache:fluss:*:*:*:*:*:*:*:*

References for CVE-2026-49361

cvelogic Threat Intelligence