etcd is a distributed key-value store for the data of a distributed system. Prior to versions 3.5.33, 3.6.14, and 3.7.1, a network attacker who can reach an etcd TLS listener can open many TCP connections and never send a ClientHello. In client/pkg/transport/listener_tls.go, each connection handled by tlsListener.acceptLoop spawns a goroutine that blocks indefinitely inside tls.Conn.Handshake() and remains tracked in the pending map. Unbounded goroutine and map growth can exhaust memory in the etcd process, causing loss of availability for the cluster and, when etcd backs Kubernetes, the control plane. This issue is fixed in versions 3.5.33, 3.6.14, and 3.7.1.

An update of the etcd package has been released.

The remote Redhat Enterprise Linux 8 host has packages installed that are affected by multiple vulnerabilities as referenced in the RHSA-2026:90330 advisory.

    Red Hat OpenStack Platform provides the facilities for building, deploying and monitoring a private or     public infrastructure-as-a-service (IaaS) cloud running on commonly available physical hardware.

    Security Fix(es):

    * golang: crypto/x509: Man-in-the-middle attacks via untrusted intermediate     certificates (CVE-2026-111943)

    * golang: Go encoding/asn1: Denial of Service via excessive recursion in     Unmarshal (CVE-2026-33818)

    * golang.org/x/text: Denial of Service via invalid UTF-8 input     (CVE-2026-56852)

    * golang: Go net/http: Unencrypted HTTP/2 connections vulnerable to Denial     of Service (CVE-2026-56853)

    * golang: Go html/template: Cross-Site Scripting via pathological input     (CVE-2026-56858)

    * golang: golang net/url: Denial of Service from quadratic complexity in     path resolution (CVE-2026-56860)

    * golang: Golang crypto/tls: Denial of Service via indefinite KeyUpdate     messages (CVE-2026-56862)

    * etcd: Denial of Service via unbounded TLS handshake goroutines     (CVE-2026-73500)

    * net/http/internal/http2: golang.org/x/net/http2: net/http: Denial of     Service via excessive HTTP/2 SETTINGS frames (CVE-2026-78669)

    For more details about the security issue(s), including the impact, a CVSS     score, acknowledgments, and other related information, refer to the CVE     page listed in the References section.

Tenable has extracted the preceding description block directly from the Red Hat Enterprise Linux security advisory.

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

The remote Redhat Enterprise Linux 9 host has packages installed that are affected by multiple vulnerabilities as referenced in the RHSA-2026:90329 advisory.

    Red Hat OpenStack Platform provides the facilities for building, deploying and monitoring a private or     public infrastructure-as-a-service (IaaS) cloud running on commonly available physical hardware.

    Security Fix(es):

    * golang: crypto/x509: Man-in-the-middle attacks via untrusted intermediate     certificates (CVE-2026-111943)

    * net/url: Memory exhaustion in query parameter parsing in net/url     (CVE-2025-61726)

    * Incorrect parsing of IPv6 host literals in net/url (CVE-2026-25679)

    * golang: golang crypto/x509: Denial of Service via excessive processing of     DNS SAN entries (CVE-2026-27145)

    * crypto/tls: golang: Go: Denial of Service vulnerability in certificate     chain building (CVE-2026-32280)

    * golang: Go crypto/tls: Denial of Service via multiple TLS 1.3 key update     messages (CVE-2026-32283)

    * golang: Go net package: Denial of Service via long CNAME response in     LookupCNAME (CVE-2026-33811)

    * golang: Go encoding/asn1: Denial of Service via excessive recursion in     Unmarshal (CVE-2026-33818)

    * golang: net/http: golang.org/x/net/idna: Privilege escalation via     incorrect Punycode label processing (CVE-2026-39821)

    * golang: Go net/http: Unencrypted HTTP/2 connections vulnerable to Denial     of Service (CVE-2026-56853)

    * golang: Go html/template: Cross-Site Scripting via pathological input     (CVE-2026-56858)

    * golang: golang net/url: Denial of Service from quadratic complexity in     path resolution (CVE-2026-56860)

    * golang: Golang crypto/tls: Denial of Service via indefinite KeyUpdate     messages (CVE-2026-56862)

    * etcd: Denial of Service via unbounded TLS handshake goroutines     (CVE-2026-73500)

    * net/http/internal/http2: golang.org/x/net/http2: net/http: Denial of     Service via excessive HTTP/2 SETTINGS frames (CVE-2026-78669)

    For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and     other related information, refer to the CVE page listed in the References section.

Tenable has extracted the preceding description block directly from the Red Hat Enterprise Linux security advisory.

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

There are packages installed that are affected by a vulnerability referenced in the following CVE:

  - etcd is a distributed key-value store for the data of a distributed system. Prior to versions 3.5.33,
    3.6.14, and 3.7.1, a network attacker who can reach an etcd TLS listener can open many TCP connections and
    never send a ClientHello. In client/pkg/transport/listener_tls.go, each connection handled by
    tlsListener.acceptLoop spawns a goroutine that blocks indefinitely inside tls.Conn.Handshake() and remains
    tracked in the pending map. Unbounded goroutine and map growth can exhaust memory in the etcd process,
    causing loss of availability for the cluster and, when etcd backs Kubernetes, the control plane. This
    issue is fixed in versions 3.5.33, 3.6.14, and 3.7.1. (CVE-2026-73500)

The version of Tencent Linux installed on the remote TencentOS Server 4 host is prior to tested version. It is, therefore, affected by a vulnerability as referenced in the TSSA-2026:0852 advisory.

    Package updates are available for TencentOS Server 4 that fix the following vulnerabilities:

    CVE-2026-73500:
    etcd is a distributed key-value store for the data of a distributed system. Prior to versions 3.5.33,     3.6.14, and 3.7.1, a network attacker who can reach an etcd TLS listener can open many TCP connections and     never send a ClientHello. In client/pkg/transport/listener_tls.go, each connection handled by     tlsListener.acceptLoop spawns a goroutine that blocks indefinitely inside tls.Conn.Handshake() and remains     tracked in the pending map. Unbounded goroutine and map growth can exhaust memory in the etcd process,     causing loss of availability for the cluster and, when etcd backs Kubernetes, the control plane.

Tenable has extracted the preceding description block directly from the Tencent Linux security advisory.

Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version number.

The Linux/Unix host has one or more packages installed that are impacted by a vulnerability without a vendor supplied patch available.

  - etcd is a distributed key-value store for the data of a distributed system. Prior to versions 3.5.33,     3.6.14, and 3.7.1, a network attacker who can reach an etcd TLS listener can open many TCP connections and     never send a ClientHello. In client/pkg/transport/listener_tls.go, each connection handled by     tlsListener.acceptLoop spawns a goroutine that blocks indefinitely inside tls.Conn.Handshake() and remains     tracked in the pending map. Unbounded goroutine and map growth can exhaust memory in the etcd process,     causing loss of availability for the cluster and, when etcd backs Kubernetes, the control plane. This     issue is fixed in versions 3.5.33, 3.6.14, and 3.7.1. (CVE-2026-73500)

Note that Nessus relies on the presence of the package as reported by the vendor.

ID	Name	Product	Family	Type	Severity
375618	Photon OS 5.0: Etcd PHSA-2026-5.0-92-0975	Nessus	PhotonOS Local Security Checks	Local	high
374984	Photon OS 5.0: Etcd PHSA-2026-5.0-91-0975	Nessus	PhotonOS Local Security Checks	Local	high
373591	RHEL 8 : Red Hat OpenStack Platform 16.2 security advisory (Important) (RHSA-2026:90330)	Nessus	Red Hat Local Security Checks	Local	high
372143	RHEL 9 : Red Hat OpenStack Platform 17.1 security advisory (Important) (RHSA-2026:90329)	Nessus	Red Hat Local Security Checks	Local	high
465768	Echo: go.etcd.io/etcd/client/pkg/v3: security update to 3.5.33	Tenable Cloud Security	Echo Local Security Checks	Local	high
465768	Echo: go.etcd.io/etcd/client/pkg/v3: security update to 3.5.33	Tenable Self-Hosted Container Security	Echo Local Security Checks	Local	high
339170	TencentOS Server 4: etcd (TSSA-2026:0852)	Nessus	Tencent Local Security Checks	Local	high
445912	SCA: security update for go.etcd.io/etcd/v3 (GHSA-6vch-q96h-7gc3)	Tenable Cloud Security	SCA Checks	Local	high
445912	SCA: security update for go.etcd.io/etcd/v3 (GHSA-6vch-q96h-7gc3)	Tenable Self-Hosted Container Security	SCA Checks	Local	high
335145	Linux Distros Unpatched Vulnerability : CVE-2026-73500	Nessus	Misc.	Local	high

Detections

Analytics

CVE-2026-73500

high

Tenable Plugins

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high

high

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high

high

high

high

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high