CVE-2026-73553

HIGHPre-NVD 7.57.5—
EchelonGraph scoreMEDIUM confidence

This high-severity CVE scores 7.5 under a secondary CVSS source (NVD's own analysis pending). EPSS exploit probability: 0.5%, top 57% 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 — 4 sources updated this weekElevated
7.5EG
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 1%CVSS: 7.5Exploit: Elevated riskExposed: 0

A fix is available — apply it.

Envoy is an open source edge and service proxy designed for cloud-native applications. Prior to 1.36.10, 1.37.6, 1.38.4, and 1.39.1, When ignore_path_parameters_in_path_matching is enabled, Envoy's router strips the semicolon suffix before matching but the RBAC url_path matcher evaluates the raw path. A downstream request such as /admin;x can therefore miss a DENY rule for /admin while the router still selects the protected /admin backend. The inconsistent canonicalization allows an unauthenticated client to bypass path-based authorization. The relevant scope boundary is that the route option and a path-based RBAC rule must both be present, and the protected route must match after stripping. This issue is fixed in versions 1.36.10, 1.37.6, 1.38.4, and 1.39.1.

CVSS v3
7.5
EG Score
7.5(medium)
EG Risk
50(Track)
EG Risk 50/100SSVC: 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
Severity75% × 45%
Exploitation40% × 40%
Automatability0% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
1%
EPSS %ILE
43%
KEV
Not listed

Published

September 21, 2026

Last Modified

September 23, 2026

Advisory Details (9)

Auto-updated Sep 21, 2026
🔬 Proof of concept available. Patch available. Sources: github_release, github, github_commit.
github Patch Available🟡 PoC Available

Path Parameter Canonicalization Bypasses Path-Based Security Rules · Advisory · envoyproxy/envoy · GitHub

https://github.com/envoyproxy/envoy/security/advisories/GHSA-77x5-xqjg-hprq
github_release Patch Available

v1.39.1

Patch available: envoyproxy/envoy v1.39.1

https://github.com/envoyproxy/envoy/releases/tag/v1.39.1
github_release Patch Available

v1.38.4

Patch available: envoyproxy/envoy v1.38.4

https://github.com/envoyproxy/envoy/releases/tag/v1.38.4
github_release Patch Available

v1.37.6

Patch available: envoyproxy/envoy v1.37.6

https://github.com/envoyproxy/envoy/releases/tag/v1.37.6
github_release Patch Available

v1.36.10

Patch available: envoyproxy/envoy v1.36.10

https://github.com/envoyproxy/envoy/releases/tag/v1.36.10
github_commit

commit e6d5fe885409 (envoyproxy/envoy)

Fix landed in envoyproxy/envoy commit e6d5fe885409 — awaiting tagged release

https://github.com/envoyproxy/envoy/commit/e6d5fe885409ebb335ed3934a167f0bcfea471f2
github_commit

commit b6ec9b66cc33 (envoyproxy/envoy)

Fix landed in envoyproxy/envoy commit b6ec9b66cc33 — awaiting tagged release

https://github.com/envoyproxy/envoy/commit/b6ec9b66cc33a415e2fa81a6fa8363cac4772dd1
github_commit

commit 6a703a375a20 (envoyproxy/envoy)

Fix landed in envoyproxy/envoy commit 6a703a375a20 — awaiting tagged release

https://github.com/envoyproxy/envoy/commit/6a703a375a20e3bf98140ee5f5522c614adee7b6
github_commit

commit 0be4a0302ea9 (envoyproxy/envoy)

Fix landed in envoyproxy/envoy commit 0be4a0302ea9 — awaiting tagged release

https://github.com/envoyproxy/envoy/commit/0be4a0302ea94a894e470817c2edfbd5ed90d273

Vendor Advisories for CVE-2026-73553(6)

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

Patch Availability(5)

Vendor / EcosystemFixed in / PatchReleasedSource
redhatopenshift-service-mesh/istio-proxyv2-rhel9:17882963282026-09-08redhat
redhatopenshift-service-mesh/istio-proxyv2-rhel9:17882947152026-09-08redhat
redhatopenshift-service-mesh/istio-proxyv2-rhel9:17883293662026-09-08redhat
redhatopenshift-service-mesh/istio-proxyv2-rhel9:17883278662026-09-08redhat
redhatopenshift-service-mesh/istio-proxyv2-rhel9:17883339242026-09-08redhat

Patches are aggregated from vendor advisories (Red Hat, Microsoft, Cisco, GitHub) and package ecosystems (OSV, GHSA). Multiple rows for the same upstream release have been deduplicated.

Weakness Classification(1)

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

Data Freshness Timeline

(refreshed 16× in last 7d / 16× 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. 2026-09-23 18:45 UTCEG score recompute
  2. 2026-09-23 18:45 UTCVendor advisory
  3. 2026-09-23 17:54 UTCEPSS rescore
  4. 2026-09-23 12:36 UTCVendor advisory
  5. 2026-09-23 01:28 UTCEG score recompute
  6. 2026-09-23 01:28 UTCVendor advisory
  7. 2026-09-22 14:20 UTCEG score recompute
  8. 2026-09-22 14:20 UTCVendor advisory
  9. 2026-09-22 13:36 UTCEG score recompute
  10. 2026-09-22 13:36 UTCVendor advisory
  11. 2026-09-22 08:30 UTCVendor advisory
  12. 2026-09-21 21:22 UTCEG score recompute
  13. 2026-09-21 21:22 UTCVendor advisory
  14. 2026-09-21 20:25 UTCEG score recompute
  15. 2026-09-21 20:25 UTCVendor advisory
  16. 2026-09-21 20:23 UTCMITRE cvelistV5first tracked

Related CVEs(same vendor + same CWE)

Frequently asked(5)

What is CVE-2026-73553?
CVE-2026-73553 is a high vulnerability published on September 21, 2026. Envoy is an open source edge and service proxy designed for cloud-native applications. Prior to 1.36.10, 1.37.6, 1.38.4, and 1.39.1, When ignorepathparametersinpathmatching is enabled, Envoy's router strips the semicolon suffix before matching but the RBAC urlpath matcher evaluates the raw path. A…
When was CVE-2026-73553 disclosed?
CVE-2026-73553 was first published in the National Vulnerability Database on September 21, 2026, with the most recent update on September 23, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-73553 actively exploited?
CVE-2026-73553 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 1% probability of exploitation in the next 30 days, which ranks it in the top 57.0% of all scored CVEs.
What is the CVSS score of CVE-2026-73553?
CVE-2026-73553 has a CVSS v3 base score of 7.5 (NVD).
How do I remediate CVE-2026-73553?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-73553, 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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