CVE-2021-29258

envoyproxy/envoy: crash with empty HTTP/2 metadata map

Severity Score

7.5

*CVSS v3.1

Exploit Likelihood

*EPSS

Affected Versions

*CPE

Public Exploits

*Multiple Sources

Exploited in Wild

*KEV

Decision

*SSVC

Descriptions

An issue was discovered in Envoy 1.14.0. There is a remotely exploitable crash for HTTP2 Metadata, because an empty METADATA map triggers a Reachable Assertion.

Se detectó un problema en Envoy versión 1.14.0. Se presenta un bloqueo explotable remoto para unos metadatos HTTP2, porque un mapa de METADATOS vacío desencadena un Reachable Assertion

A flaw was found in envoyproxy. An attacker, able to craft an HTTP2 request that specifies an empty metadata map, can crash envoy resulting in a denial of service due to the null reference. The highest threat from this vulnerability is to system availability.

Red Hat OpenShift Service Mesh is Red Hat's distribution of the Istio service mesh project, tailored for installation into an on-premise OpenShift Container Platform installation. Issues addressed include integer overflow and null pointer vulnerabilities.

*Credits: N/A

Attack Vector

Network

Attack Complexity

Low

Privileges Required

None

User Interaction

None

Scope

Unchanged

Confidentiality

None

Integrity

None

Availability

High

Attack Vector

Network

Attack Complexity

Low

Authentication

None

Confidentiality

None

Integrity

None

Availability

Partial

* Common Vulnerability Scoring System

SSVC

Decision:-

Exploitation

Automatable

Tech. Impact

* Organization's Worst-case Scenario

Timeline

2021-03-26 CVE Reserved
2021-04-22 CVE Published
2024-08-03 CVE Updated
2025-03-30 EPSS Updated
---------- Exploited in Wild
---------- KEV Due Date
---------- First Exploit

CWE

CWE-476: NULL Pointer Dereference
CWE-617: Reachable Assertion

CAPEC

References (7)

URL	Tag	Source
https://github.com/envoyproxy/envoy-setec/pull/230	Broken Link
https://github.com/envoyproxy/envoy/releases/tag/v1.14.0	Third Party Advisory
https://github.com/envoyproxy/envoy/security/advisories/GHSA-rqvq-hxw5-776j	Third Party Advisory
https://github.com/envoyproxy/envoy/security/advisories/GHSA-xw4q-6pj2-5gfg	Not Applicable

URL	Date	SRC

URL	Date	SRC

URL	Date	SRC
https://blog.envoyproxy.io	2021-05-27
https://access.redhat.com/security/cve/CVE-2021-29258	2021-04-22
https://bugzilla.redhat.com/show_bug.cgi?id=1942280	2021-04-22

Affected Vendors, Products, and Versions

Vendor		Product				Version		Other		Status
Vendor	Product	Version	Other	Status	<-- -->	Vendor	Product	Version	Other	Status
Envoyproxy Search vendor "Envoyproxy"		Envoy Search vendor "Envoyproxy" for product "Envoy"				1.14.6 Search vendor "Envoyproxy" for product "Envoy" and version "1.14.6"		-		Affected
Envoyproxy Search vendor "Envoyproxy"		Envoy Search vendor "Envoyproxy" for product "Envoy"				1.15.3 Search vendor "Envoyproxy" for product "Envoy" and version "1.15.3"		-		Affected
Envoyproxy Search vendor "Envoyproxy"		Envoy Search vendor "Envoyproxy" for product "Envoy"				1.16.2 Search vendor "Envoyproxy" for product "Envoy" and version "1.16.2"		-		Affected
Envoyproxy Search vendor "Envoyproxy"		Envoy Search vendor "Envoyproxy" for product "Envoy"				1.17.1 Search vendor "Envoyproxy" for product "Envoy" and version "1.17.1"		-		Affected