A HTTP request smuggling and desynchronization vulnerability affects Kong Gateway Enterprise 3.4, 3.10, 3.11, 3.12, 3.13, and 3.14 series. The vulnerability is caused by a parsing flaw in Kong’s HTTP request processing pipeline when handling untrusted HTTP/1.1 traffic.
CVE-2026-6338
MEDIUMPre-NVD 4.94.9—
EchelonGraph scoreMEDIUM confidence
This medium-severity CVE scores 4.9 under a secondary CVSS source (NVD's own analysis pending). EPSS exploit probability: 0.3%, top 83% 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
4.9
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
- Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS: 0%CVSS: 4.9Exploit: NoneExposed: 0
No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.
- CVSS v3
- 4.9
- EG Score
- 4.9(medium)
- EPSS
- 16.6%
- KEV
- Not listed
Published
June 11, 2026
Last Modified
June 11, 2026
Advisory Details (1)
Auto-updated Jun 15, 2026No patch confirmed yet.
Vendor Advisories for CVE-2026-6338(1)
These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.
Frequently asked(5)
What is CVE-2026-6338?
CVE-2026-6338 is a medium vulnerability published on June 11, 2026. A HTTP request smuggling and desynchronization vulnerability affects Kong Gateway Enterprise 3.4, 3.10, 3.11, 3.12, 3.13, and 3.14 series. The vulnerability is caused by a parsing flaw in Kong’s HTTP request processing pipeline when handling untrusted HTTP/1.1 traffic.
When was CVE-2026-6338 disclosed?
CVE-2026-6338 was first published in the National Vulnerability Database on June 11, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-6338 actively exploited?
CVE-2026-6338 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 16.6% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.
What is the CVSS score of CVE-2026-6338?
CVE-2026-6338 has a CVSS v3 base score of 4.9 (NVD).
How do I remediate CVE-2026-6338?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-6338, 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
Explore the affected products and dependency analysis for CVE-2026-6338
Is Your Infrastructure Affected by CVE-2026-6338?
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