Cilium is a networking, observability, and security solution. Prior to 1.17.17, 1.18.11, and 1.19.5, Cilium clusters using Gateway API allow users with permissions to create or update namespaced HTTPRoutes to mirror HTTP traffic to any Service in any namespace, bypassing the ReferenceGrant authorization mechanism. Gateway API functionality is disabled by default. This issue is fixed in versions 1.17.17, 1.18.11, and 1.19.5.
CVE-2026-56742
MEDIUMPre-NVD 5.95.9
EchelonGraph scoreLOW confidence
This medium-severity CVE scores 5.9 under the CNA's CVSS (NVD's own analysis pending). EPSS exploit-prediction score not yet available (the EPSS model rescores nightly; freshly-published CVEs typically appear within 48 hours). 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: cna:github_m
5.9
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
- Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS: —CVSS: 5.9Exploit: NoneExposed: 0
No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.
- CVSS v3
- 5.9
- EG Score
- 5.9(low)
- EPSS
- —
- KEV
- Not listed
Published
July 15, 2026
Last Modified
July 15, 2026
Advisory Details (8)
Auto-updated Jul 15, 2026Patch available. Sources: github_commit, github_release, github.
github Patch Available
Namespaced HTTPRoutes can redirect traffic to other namespaces · Advisory · cilium/cilium · GitHub
https://github.com/cilium/cilium/security/advisories/GHSA-w7c2-w76w-5hmjgithub_release Patch Available
1.19.5
Patch available: cilium/cilium v1.19.5
https://github.com/cilium/cilium/releases/tag/v1.19.5github_release Patch Available
1.18.11
Patch available: cilium/cilium v1.18.11
https://github.com/cilium/cilium/releases/tag/v1.18.11github_release Patch Available
1.17.17
Patch available: cilium/cilium v1.17.17
https://github.com/cilium/cilium/releases/tag/v1.17.17github_commit
commit fd47963ea394 (cilium/cilium)
Fix landed in cilium/cilium commit fd47963ea394 — awaiting tagged release
https://github.com/cilium/cilium/commit/fd47963ea394d5e8fa4a88c40a79063430c512cagithub_commit
commit f23929cff682 (cilium/cilium)
Fix landed in cilium/cilium commit f23929cff682 — awaiting tagged release
https://github.com/cilium/cilium/commit/f23929cff682d6ed0dc158070812cb302fc0032bgithub_commit
commit e0b1cef513ff (cilium/cilium)
Fix landed in cilium/cilium commit e0b1cef513ff — awaiting tagged release
https://github.com/cilium/cilium/commit/e0b1cef513ff910323f3743e9f3e3d86721e4857github_commit
commit 7422068aff67 (cilium/cilium)
Fix landed in cilium/cilium commit 7422068aff67 — awaiting tagged release
https://github.com/cilium/cilium/commit/7422068aff67ac77c7dcc57aa5b9240c91333debWeakness Classification(1)
MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.
Data Freshness Timeline
(refreshed 2× in last 7d / 2× 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.
- 2026-07-15 19:45 UTCEG score recompute
- 2026-07-15 19:44 UTCMITRE cvelistV5first tracked
Frequently asked(4)
What is CVE-2026-56742?
CVE-2026-56742 is a medium vulnerability published on July 15, 2026. Cilium is a networking, observability, and security solution. Prior to 1.17.17, 1.18.11, and 1.19.5, Cilium clusters using Gateway API allow users with permissions to create or update namespaced HTTPRoutes to mirror HTTP traffic to any Service in any namespace, bypassing the ReferenceGrant…
When was CVE-2026-56742 disclosed?
CVE-2026-56742 was first published in the National Vulnerability Database on July 15, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
What is the CVSS score of CVE-2026-56742?
CVE-2026-56742 has a CVSS v3 base score of 5.9 (NVD). The EG score is currently aggregating — additional source signals are being incorporated as they become available..
How do I remediate CVE-2026-56742?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-56742, 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-2026-56742
Is Your Infrastructure Affected by CVE-2026-56742?
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