CVE-2026-53718

MEDIUMPre-NVD 6.46.4
EchelonGraph scoreMEDIUM confidence

“—” beside the score: it is equal to the CVSS score beside it.

This medium-severity CVE scores 6.4 under a secondary CVSS source (NVD's own analysis pending). EPSS exploit probability: 0.4% (35th percentile of EPSS-scored CVEs). No GitHub Security Advisory CVSS is on record for this CVE.

Triggered by: Headline CVSS from a secondary CVSS source
Sources: EPSS, a secondary CVSS source

Also known asEUVD-2026-78072 (ENISA EUVD) · GHSA-fcrp-7gc2-93g7 (GitHub Security Advisories)Source: ENISA EUVD

6.4EG
EchelonGraph verdictMonitorRemediate within your standard update timelines (the SSVC decision on this page).
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS PROB: 0.4%CVSS: 6.4Exploit: None knownExposed services: Not assessed

A fix is available — apply it.

Envoy Gateway is an open source project for managing Envoy Proxy as a standalone or Kubernetes-based application gateway. Prior to 1.7.4 and 1.8.1, an HTTPRoute can use an extension-managed custom backendRef to reference a backend resource in another namespace without a matching Gateway API ReferenceGrant in the target namespace. The custom-backend branch in internal/gatewayapi/route.go omits validateBackendNamespace, allowing the route-owning namespace to bind to and use the resource without the backend namespace owner's consent and violating the Gateway API cross-namespace authorization model. This issue is fixed in versions 1.7.4 and 1.8.1.

CVSS v3
6.4
EG Score
6.4MEDIUMmedium confidence
EG Risk
29
EG Risk 29/100

EG Risk is EchelonGraph's 0–100 priority score. It fuses impact severity (EG Severity, the CVSS base score, never the KEV-floored or EPSS-lifted EG Score) with real-world exploitation and automatability, under weights EchelonGraph set by hand, so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner.

How it’s computed (value × EchelonGraph’s weight)
Severity64% × 45%
Impact severity (EG Severity): CVSS 6.4 of 10. Never the KEV-floored or EPSS-lifted EG Score.
Exploitation0.4% × 40%
FIRST EPSS: the 30-day exploitation probability when EchelonGraph scored this CVE.
Automatability0% × 15%
CISA's SSVC Automatable value: no (Vulnrichment).
SSVC (CISA's decision table, applied by EchelonGraph): Track at every mission impact level.
Exploitation none (CISA Vulnrichment) · Automatable no (CISA Vulnrichment) · Technical impact partial (CISA Vulnrichment). All three are CISA's SSVC values (Vulnrichment). EchelonGraph applied CISA's decision table to them; CISA publishes SSVC inputs and the table, not a decision for each CVE.
Action: A fix is available. Apply it within your standard update timelines.
EPSS PROB
0.4%
EPSS %ILE
35th
KEV
Not listed

What the EG score is made of (scorer v4.0: the three questions the 0–10 score mixes, published apart · methodology)

The EG score (6.4): severity, escalated by confirmed exploitation. This CVE's 6.4 is its impact severity (EG Severity), not escalated.

EG Severity
6.4 MEDIUMCVSS-B, impact only: no KEV listing, EPSS or EG-KEV tier raises it.a secondary CVSS source · CVSS v3.0 or v3.1
EG Likelihood
0.4% within 30 daysSource: FIRST EPSS (model v2026.06.15, score date 2026-10-24). FIRST's exploitation probability, not an EchelonGraph model.
Confirmed exploitation
None on record (CISA KEV, EG-KEV Tier 1)Reported apart from the likelihood: an observed fact, not a probability.
EG Priority
SSVC Track at medium mission impactTrack at every mission impact level.CISA BOD 26-04: 60 days if the affected system is publicly exposed; Fix on system upgrade if it is not.Each input and its source: the SSVC and BOD 26-04 blocks below.

SSVC (CISA's decision table, applied by EchelonGraph)Track at every mission impact level.

A fix is available. Apply it within your standard update timelines.

Exploitation none (CISA Vulnrichment) · Automatable no (CISA Vulnrichment) · Technical impact partial (CISA Vulnrichment). All three are CISA's SSVC values (Vulnrichment). EchelonGraph applied CISA's decision table to them; CISA publishes SSVC inputs and the table, not a decision for each CVE. Mission impact is CISA's Mission & Well-being decision point, and only you can judge it. CISA's table makes it high when Mission Prevalence is Essential — the vulnerable component "directly provides capabilities that constitute at least one MEF for at least one entity" (MEF: mission essential function) — or when Public Well-Being Impact is Irreversible: "multiple fatalities are likely", the cyber-physical system "is likely lost or destroyed", "extreme or serious externalities" are imposed on other parties, or social systems such as elections or the financial grid "are destabilized and potentially collapse". CISA's decision table

BOD 26-04 (CISA's remediation timeline, Table 1)60 days if the affected system is publicly exposed; Fix on system upgrade if it is not.

In CISA KEV no (CISA's KEV catalog) · Automatable no (CISA Vulnrichment) · Technical impact partial (CISA Vulnrichment). Whether your system is publicly exposed is yours to answer. BOD 26-04 binds US Federal Civilian Executive Branch agencies; for anyone else it is CISA's published timeline, a reference rather than an obligation. The directive · how EchelonGraph applies it

Published

July 16, 2026

Last Modified

September 25, 2026

Advisory Details (9)

Auto-updated Sep 14, 2026
Patch available. Sources: github, github_pr, github_commit, github_release.
GitHub release Patch Available

v1.8.1

Patch available: envoyproxy/gateway v1.8.1

https://github.com/envoyproxy/gateway/releases/tag/v1.8.1
GitHub release Patch Available

v1.7.4

Patch available: envoyproxy/gateway v1.7.4

https://github.com/envoyproxy/gateway/releases/tag/v1.7.4
GitHub commit

commit b4737180c7e5 (envoyproxy/gateway)

Fix landed in envoyproxy/gateway commit b4737180c7e5 — awaiting tagged release

https://github.com/envoyproxy/gateway/commit/b4737180c7e597490c6363075c565fa8cf24eead
GitHub commit

commit 96e2b750868a (envoyproxy/gateway)

Fix landed in envoyproxy/gateway commit 96e2b750868a — awaiting tagged release

https://github.com/envoyproxy/gateway/commit/96e2b750868a459ace4b8b68e6a6e4fb0152b9b7
GitHub commit

commit 5a78db82b7cf (envoyproxy/gateway)

Fix landed in envoyproxy/gateway commit 5a78db82b7cf — awaiting tagged release

https://github.com/envoyproxy/gateway/commit/5a78db82b7cf4fc5bebbeda2c50952892038a464
GitHub pull request

fix github SA for June release

Fix merged in envoyproxy/gateway PR #9173 on 2026-06-05 — awaiting tagged release

https://github.com/envoyproxy/gateway/pull/9173
GitHub pull request

[release-1.8] fix github SA for June release

Fix merged in envoyproxy/gateway PR #9172 on 2026-06-05 — awaiting tagged release

https://github.com/envoyproxy/gateway/pull/9172
GitHub pull request

[release-1.7] fix github SA for June release

Fix merged in envoyproxy/gateway PR #9171 on 2026-06-05 — awaiting tagged release

https://github.com/envoyproxy/gateway/pull/9171
GitHub advisoryMentions a patch (unverified)

Envoy Gateway custom backendRef cross-namespace ReferenceGrant bypass · Advisory · envoyproxy/gateway · GitHub

https://github.com/envoyproxy/gateway/security/advisories/GHSA-fcrp-7gc2-93g7

Vendor Advisories for CVE-2026-53718(1)

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

Affected Packages

(1 across 1 ecosystem)
Go(1)
PackageVulnerable rangeFix by version rangeDependents
github.com/envoyproxy/gateway—
  • 1.8.0-rc.0 up to 1.8.1: fixed in 1.8.1
  • every version up to 1.7.4: fixed in 1.7.4
—

Weakness Classification(1)

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

Data Freshness Timeline

(refreshed 9× in last 7d / 38× in last 30d)

Each row is a time one of our pipelines fetched, updated or re-scored this CVE. 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. An arrow marks a change the record states ("CVSS v3 → 9.1"); EPSS and GHSA rows show the values recorded at that time, not what changed (EPSS values are rounded; hover one for the exact figures). Most recent first.

  1. 2026-10-26 16:31 UTCEPSS rescoreEPSS 0.4% · 35th percentile
  2. 2026-10-25 16:33 UTCEPSS rescoreEPSS 0.4% · 35th percentile
  3. 2026-10-25 14:20 UTCEG score recompute
  4. 2026-10-24 16:33 UTCEPSS rescoreEPSS 0.4% · 34th percentile
  5. 2026-10-23 16:32 UTCEPSS rescoreEPSS 0.4% · 34th percentile
  6. 2026-10-22 21:47 UTCEG score recompute
  7. 2026-10-22 16:34 UTCEPSS rescoreEPSS 0.4% · 34th percentile
  8. 2026-10-21 16:33 UTCEPSS rescoreEPSS 0.4% · 34th percentile
  9. 2026-10-20 16:33 UTCEPSS rescoreEPSS 0.4% · 34th percentile
  10. 2026-10-19 16:32 UTCEPSS rescoreEPSS 0.4% · 34th percentile
  11. 2026-10-18 16:32 UTCEPSS rescoreEPSS 0.4% · 34th percentile
  12. 2026-10-18 03:31 UTCEG score recompute
  13. 2026-10-17 16:34 UTCEPSS rescoreEPSS 0.4% · 34th percentile
  14. 2026-10-16 16:42 UTCEPSS rescoreEPSS 0.4% · 34th percentile
  15. 2026-10-15 16:32 UTCEPSS rescoreEPSS 0.4% · 34th percentile
  16. 2026-10-14 16:33 UTCEPSS rescoreEPSS 0.4% · 33rd percentile
  17. 2026-10-13 16:34 UTCEPSS rescoreEPSS 0.4% · 33rd percentile
  18. 2026-10-12 16:34 UTCEPSS rescoreEPSS 0.4% · 33rd percentile
  19. 2026-10-12 15:57 UTCEG score recompute
  20. 2026-10-11 19:40 UTCEG score recompute
  21. 2026-10-11 16:55 UTCEG score recompute
  22. 2026-10-11 14:18 UTCEG score recompute
  23. 2026-10-11 13:49 UTCEPSS rescoreEPSS 0.4% · 33rd percentile
  24. 2026-10-10 20:00 UTCEPSS rescoreEPSS 0.4% · 33rd percentile
  25. 2026-10-09 20:07 UTCEPSS rescoreEPSS 0.4% · 33rd percentile
Show 31 more
  1. 2026-10-08 17:12 UTCEPSS rescoreEPSS 0.4% · 33rd percentile
  2. 2026-10-07 23:48 UTCEPSS rescoreEPSS 0.4% · 33rd percentile
  3. 2026-10-06 15:18 UTCEPSS rescoreEPSS 0.4% · 33rd percentile
  4. 2026-10-05 17:43 UTCEPSS rescoreEPSS 0.4% · 33rd percentile
  5. 2026-10-04 23:22 UTCEPSS rescoreEPSS 0.4% · 33rd percentile
  6. 2026-10-03 14:26 UTCEPSS rescoreEPSS 0.4% · 33rd percentile
  7. 2026-10-02 17:56 UTCEPSS rescoreEPSS 0.4% · 33rd percentile
  8. 2026-10-01 19:50 UTCEPSS rescoreEPSS 0.4% · 33rd percentile
  9. 2026-10-01 11:22 UTCEG score recompute
  10. 2026-09-30 15:03 UTCEPSS rescoreEPSS 0.4% · 33rd percentile
  11. 2026-09-29 15:22 UTCEPSS rescoreEPSS 0.4% · 33rd percentile
  12. 2026-09-28 13:51 UTCEPSS rescoreEPSS 0.4% · 33rd percentile
  13. 2026-09-28 08:16 UTCEG score recompute
  14. 2026-09-27 13:48 UTCEPSS rescoreEPSS 0.4% · 33rd percentile
  15. 2026-09-26 15:59 UTCEPSS rescoreEPSS 0.4% · 32nd percentile
  16. 2026-09-25 14:25 UTCEG score recompute
  17. 2026-09-24 14:04 UTCEPSS rescoreEPSS 0.4% · 32nd percentile
  18. 2026-09-23 03:01 UTCEG score recompute
  19. 2026-09-20 20:16 UTCEPSS rescoreEPSS 0.3% · 25th percentile
  20. 2026-09-18 19:28 UTCEPSS rescoreEPSS 0.3% · 25th percentile
  21. 2026-09-18 10:16 UTCEG score recompute
  22. 2026-09-17 10:29 UTCEG score recompute
  23. 2026-09-16 14:08 UTCEPSS rescoreEPSS 0.3% · 25th percentile
  24. 2026-09-16 05:15 UTCEPSS rescoreEPSS 0.3% · 25th percentile
  25. 2026-09-15 14:37 UTCEG score recompute
  26. 2026-09-15 14:04 UTCEG score recompute
  27. 2026-09-14 21:33 UTCEG score recompute
  28. 2026-07-30 10:53 UTCEG score recompute
  29. 2026-07-26 11:25 UTCEG score recompute
  30. 2026-07-23 03:19 UTCEG score recompute
  31. 2026-07-16 20:05 UTCEG score recompute

Frequently asked(5)

What is CVE-2026-53718?
CVE-2026-53718 is a medium-severity vulnerability; its CVE record was published on July 16, 2026. Envoy Gateway is an open source project for managing Envoy Proxy as a standalone or Kubernetes-based application gateway. Prior to 1.7.4 and 1.8.1, an HTTPRoute can use an extension-managed custom backendRef to reference a backend resource in another namespace without a matching Gateway API…
When was the CVE record for CVE-2026-53718 published?
The CVE record for CVE-2026-53718 was published on July 16, 2026. That is the record's publication date; the vulnerability itself may have been made public earlier. EchelonGraph's copy of the record carries a last-modified date of September 25, 2026; the record at its source may have been updated since.
Is CVE-2026-53718 actively exploited?
CVE-2026-53718 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0.4% probability of exploitation in the next 30 days (35th percentile of EPSS-scored CVEs).
What is the CVSS score of CVE-2026-53718?
CVE-2026-53718 has a CVSS base score of 6.4 (a secondary CVSS source that NVD displays; NVD's own analysis pending).
How do I remediate CVE-2026-53718?
A fix for CVE-2026-53718 is available: update to the fixed version the vendor names in its advisory. The vendor advisories EchelonGraph has for CVE-2026-53718 are linked in the Vendor Advisories panel on this page.

Dependency Blast Radius

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