CVE-2026-26309
MEDIUM EPSS 28.4%
Published Mar 10, 20263mo ago · Modified Jun 17, 20262w ago
5.3 CVSS 3.1
Published Mar 10, 2026 3mo ago
Last Modified Jun 17, 2026 2w ago
Description
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 Details
Base Score
Exploitability
Impact
Vector string
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L Attack Vector Network
Attack Complexity Low
Privileges Required None
User Interaction None
Scope Unchanged
Confidentiality None
Integrity None
Availability Low
Threat Intelligence
EPSS Exploit Probability
28.4% percentile
Exploit & Patch Status
Public Exploit Known
No Patch Available
Weaknesses 1
CWE-193
Affected Products 4
| Vendor | Product | Version | Range |
|---|---|---|---|
| envoyproxy | envoy | * | <1.34.13 |
| envoyproxy | envoy | * | ≥1.35.0 – <1.35.8 |
| envoyproxy | envoy | * | ≥1.36.0 – <1.36.5 |
| envoyproxy | envoy | 1.37.0 | any |
References 1
- github.com https://github.com/envoyproxy/envoy/security/advisories/GHSA-56cj-wgg3-x943
Remediation
No remediation data recorded yet
Check vendor advisories and the NVD entry for patch availability.