CVE-2026-63335

MEDIUMPre-NVD 6.36.3—
EchelonGraph scoreMEDIUM confidence

This medium-severity CVE scores 6.3 under a secondary CVSS source (NVD's own analysis pending). EPSS exploit probability: 0.3%, top 78% of all CVEs by exploit prediction. GitHub Security Advisory data not yet ingested — confidence will rise once GHSA publishes (typical lag: hours to days for open-source ecosystem CVEs; never for infrastructure-only CVEs).

Triggered by: NVD CVSS baseline
Sources: epss, secondary
Trending — 3 sources updated this weekElevated
6.3EG
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 6.3Exploit: Elevated riskExposed: 0

No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.

The RabbitMQ Java client library allows Java and JVM-based applications to connect to and interact with RabbitMQ nodes. Prior to 5.31.0, inbound AMQP command assembly in src/main/java/com/rabbitmq/client/impl/CommandAssembler.java processes a content-bearing method and header whose remainingBodyBytes value is smaller than a following AMQP.FRAME_BODY payload. CommandAssembler.consumeBodyFrame subtracts the peer-controlled payload length before validating that it fits, drives remainingBodyBytes negative, and throws a raw UnsupportedOperationException instead of MalformedFrameException. A malicious or compromised broker peer can send this malformed sequence on an open nonzero channel to terminate frame processing and close the client connection, causing denial of service for work using that connection. This issue is fixed in version 5.31.0.

CVSS v3
6.3
EG Score
6.3(medium)
EG Risk
44(Track)
EG Risk 44/100SSVC: Track

EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).

How it’s computed
Severity63% × 45%
Exploitation40% × 40%
Automatability0% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
0%
EPSS %ILE
22%
KEV
Not listed

Published

August 18, 2026

Last Modified

August 18, 2026

Advisory Details (6)

Auto-updated Aug 18, 2026
🔬 Proof of concept available. Patch available. Sources: github, github_pr, github_commit, github_release.
github_release Patch Available

5.31.0

Patch available: rabbitmq/rabbitmq-java-client v5.31.0

https://github.com/rabbitmq/rabbitmq-java-client/releases/tag/v5.31.0
github_commit Patch Available

commit abd6d60d4e2b (rabbitmq/rabbitmq-java-client)

Patch available: rabbitmq/rabbitmq-java-client v5.31.0 (contains commit abd6d60d4e2b)

https://github.com/rabbitmq/rabbitmq-java-client/commit/abd6d60d4e2bfc1a327dc90ab246b2e8aca1f33b
github_commit

commit 31735344d9f9 (rabbitmq/rabbitmq-java-client)

Fix landed in rabbitmq/rabbitmq-java-client commit 31735344d9f9 — awaiting tagged release

https://github.com/rabbitmq/rabbitmq-java-client/commit/31735344d9f9dfc53740b67f06e560e8846b9322
github_pr Patch Available

Implement a TODO in CommandAssembler (backport #1959)

Patch available: rabbitmq/rabbitmq-java-client v5.31.0 (PR #1960 merged 2026-05-25)

https://github.com/rabbitmq/rabbitmq-java-client/pull/1960
github_pr

Implement a TODO in CommandAssembler

Fix merged in rabbitmq/rabbitmq-java-client PR #1959 on 2026-05-25 — awaiting tagged release

https://github.com/rabbitmq/rabbitmq-java-client/pull/1959
github Patch Available🟡 PoC Available

RabbitMQ Java client malformed body frame triggers raw command assembler exception · Advisory · rabbitmq/rabbitmq-java-client · GitHub

https://github.com/rabbitmq/rabbitmq-java-client/security/advisories/GHSA-qx7j-jv8m-fppr

Vendor Advisories for CVE-2026-63335(1)

These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.

Weakness Classification(1)

MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.

Data Freshness Timeline

(refreshed 8× in last 7d / 8× in last 30d)

Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.

  1. 2026-08-20 22:55 UTCEPSS rescore
  2. 2026-08-19 19:34 UTCEG score recompute
  3. 2026-08-19 17:04 UTCEPSS rescore
  4. 2026-08-18 18:24 UTCEG score recompute
  5. 2026-08-18 17:57 UTCEG score recompute
  6. 2026-08-18 17:21 UTCEG score recompute
  7. 2026-08-18 16:35 UTCEG score recompute
  8. 2026-08-18 16:34 UTCMITRE cvelistV5first tracked

Frequently asked(5)

What is CVE-2026-63335?
CVE-2026-63335 is a medium vulnerability published on August 18, 2026. The RabbitMQ Java client library allows Java and JVM-based applications to connect to and interact with RabbitMQ nodes. Prior to 5.31.0, inbound AMQP command assembly in src/main/java/com/rabbitmq/client/impl/CommandAssembler.java processes a content-bearing method and header whose…
When was CVE-2026-63335 disclosed?
CVE-2026-63335 was first published in the National Vulnerability Database on August 18, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-63335 actively exploited?
CVE-2026-63335 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0% probability of exploitation in the next 30 days, which ranks it in the top 78.0% of all scored CVEs.
What is the CVSS score of CVE-2026-63335?
CVE-2026-63335 has a CVSS v3 base score of 6.3 (NVD).
How do I remediate CVE-2026-63335?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-63335, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.

Dependency Blast Radius

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