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CVE-2026-118262

Echo: WebSocket proxy can retain connections and handlers after client disconnect

CVSS score

8.2

EPSS probability

—

Risk score

0.8

Published

2 h ago

OverviewPublic Exploits (0)NewsroomVulnerability Timeline
Patch status has not yet been verified

Resmî kaynaklarda yeterli kanıt bulunamadı. Bu sonuç “yama yok” anlamına gelmez.

Impact on My Inventory

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Vulnerability description

DayBreach AI Explanation

Verified against sources

CVE-2026-118262: Echo WebSocket Proxy Resource Retention Vulnerability

Sources read

2

Source agreement

Tam uyum

Evidence confidence

%63

Short explanation

The Proxy middleware in the Echo Go web framework can retain handlers, copy goroutines, and network connections after a WebSocket client disconnects. Repeated connections can accumulate resources and cause denial of service.

Why does it matter?

This vulnerability allows repeated connections to accumulate resources and cause denial of service. The impact depends on proxy route accessibility, upstream behavior, and connection deadlines.

What should be done?

  • Upgrade Echo to version 4.16.1 or 5.4.1
  • Disable WebSocket proxy routes until upgrading
  • Apply bounded connection lifetimes and resource limits at the frontend and upstream
Chain of evidence and sources3 verified claims

Echo Proxy ara katmanı, istemci bağlantısı kesildikten sonra handler ve bağlantıları tutabilir.

S0 · daybreach-canonicalS1 · cvelist

Tekrarlanan bağlantılar kaynak birikmesine ve hizmet reddine neden olabilir.

S0 · daybreach-canonicalS2 · github

Bu güvenlik açığı Echo 4.16.1 ve 5.4.1 sürümlerinde giderilmiştir.

S0 · daybreach-canonicalS1 · cvelistS2 · github
Show the technical text from the sources

Echo is a Go web framework. From 4.15.0 until 4.16.1 and 5.4.1, Echo's Proxy middleware can retain a handler, copy goroutines, and network connections after a WebSocket client disconnects when the upstream keeps its connection open. The raw proxy waits for both copy directions without reliably closing the peer connection when one direction ends, including when a rejected upgrade response uses HTTP keep-alive. Repeated connections can accumulate resources and cause denial of service, depending on proxy-route accessibility, upstream behavior, and connection deadlines. This issue is fixed in 4.16.1 and 5.4.1.

CVSS vector: CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N

CWE: CWE-772

This explanation was compiled automatically from the source records. Scores, active exploitation, patch and exploit status come straight from the sources.

IMPACT: Affected Products and Software

Affected Products

The following products are affected by CVE-2026-118262 vulnerability. Where our threat engine knows the exact affected versions, they are listed below.

IDVENDORPRODUCTACTION
1labstackecho View
2gogithub.com/labstack/echo/v4 View
3gogithub.com/labstack/echo/v5 View
Total affected vendors: 2|Products: 3

RED HAT CSAF/VEX: Product Impact Check

Red Hat has not yet published a CSAF/VEX impact record for this CVE. This does not mean “not affected”.

SCORING: CVSS from Multiple Sources

CVSS Scores

The Common Vulnerability Scoring System is a standardised framework for assessing the severity of vulnerabilities in software and systems. We collect and display CVSS scores from several sources for each CVE.

SCOREVERSIONSEVERITYVECTORSOURCE
8.2CVSS V4_0HIGHCVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:NCVE CNA
8.2CVSS V40HIGHCVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:XNVD
8.2CVSS 4.0—Vector not publishedGitHub Advisory

Patch and Remediation Guide

Solution & Remediation Advisory

Patch status unknown

İncelenen resmî kaynaklarda yama durumu doğrulanamadı. Bu sonuç “yama yok” anlamına gelmez.

Confirm the affected product and version against the source evidence above.
Restrict access to internet-facing services and apply network segmentation.
Until a patch is confirmed, follow the vendor advisory; do not read an unknown status as “no patch”.
Monitor server logs and network endpoints for signs of anomalous execution.

Public exploit and active exploitation status

Verified exploit intelligence

No verified public PoC, exploit repository or Metasploit module has been found for this CVE yet.

Weakness Classification and Attack Patterns (CWE & CAPEC)

CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorises the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-118262 is associated with the following CWEs:

CWE-772: Common Weakness Enumeration Entry CWE-772

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2026-118262 weaknesses.

CAPEC-66: SQL InjectionCAPEC-126: Path TraversalCAPEC-28: OS Command Injection

Attack Vector and Accessibility

ExposureAğ üzerinden
PermissionsGerekmiyor
UserGerekmiyor

Official Sources and Advisories

https://github.com/labstack/echo/security/advisories/GHSA-9969-6676-49h5vendor-advisoryhttps://github.com/labstack/echo/commit/1855061e572ae9dab727c811d8382f266bfbaaecvendor-advisoryhttps://github.com/labstack/echo/commit/3fb0ba7e17645bb65611e2a08875d0a2f65c421fvendor-advisoryhttps://github.com/labstack/echo/releases/tag/v4.16.1vendor-advisoryhttps://github.com/labstack/echo/releases/tag/v5.4.1vendor-advisoryhttps://github.com/advisories/GHSA-9969-6676-49h5vendor-advisory

CVSS Vector Radar Chart

8.2 / 10
Attack VectorNetworkComplexityLowPrivilegesNoneUser Interact.NoneConfidentialityLowIntegrityNoneAvailabilityHigh

Vulnerability Scoring Details

CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
Attack VectorNetwork
Attack ComplexityLow
Privileges RequiredNone required
User InteractionNone required
Confidentiality (Gizlilik)Low
Integrity (Bütünlük)None
Availability (Erişilebilirlik)High

Yama durumu bilinmiyor

İncelenen resmî kaynaklarda yama durumu doğrulanamadı. Bu sonuç “yama yok” anlamına gelmez.

Follow the vendor

L
labstack logo
labstack
G
go logo
go

Weakness Type (CWE & CAPEC)

CWE-772

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CVE-2026-118262 · Echo: WebSocket proxy can retain…