CVE-2026-26309

Envoy is a high-performance edge/middle/service proxy. Prior to 1.37.1, 1.36.5, 1.35.8, and 1.34.13, an off-by-one write in Envoy::JsonEscaper::escapeString() can corrupt std::string null-termination, causing undefined behavior and potentially leading to crashes or out-of-bounds reads when the resulting string is later treated as a C-string. This vulnerability is fixed in 1.37.1, 1.36.5, 1.35.8, and 1.34.13.

CVSS v3 5.3 MEDIUM

5.3^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 3.9 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact LOW

Scope UNCHANGED

References

Link	Resource
https://github.com/envoyproxy/envoy/security/advisories/GHSA-56cj-wgg3-x943	Vendor Advisory Exploit

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:envoyproxy:envoy::::::::
	cpe:2.3:a:envoyproxy:envoy::::::::
	cpe:2.3:a:envoyproxy:envoy::::::::
	cpe:2.3:a:envoyproxy:envoy:1.37.0:::::::*

History

No history.

Information

Published : 2026-03-10 20:16

Updated : 2026-03-11 16:14

NVD link : CVE-2026-26309

Mitre link : CVE-2026-26309

CVE.ORG link : CVE-2026-26309

JSON object : View

Products Affected

envoyproxy

envoy

CWE

CWE-193

Off-by-one Error

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