CVE-2025-62409
MEDIUM EPSS 33.3%
Published Oct 16, 20258mo ago · Modified Jun 17, 20262w ago
6.6 CVSS 4.0
Published Oct 16, 2025 8mo ago
Last Modified Jun 17, 2026 2w ago
Description
Envoy is a cloud-native, open source edge and service proxy. Prior to 1.36.1, 1.35.5, 1.34.9, and 1.33.10, large requests and responses can potentially trigger TCP connection pool crashes due to flow control management in Envoy. It will happen when the connection is closing but upstream data is still coming, resulting in a buffer watermark callback nullptr reference. The vulnerability impacts TCP proxy and HTTP 1 & 2 mixed use cases based on ALPN. This vulnerability is fixed in 1.36.1, 1.35.5, 1.34.9, and 1.33.10.
CVSS Details
Base Score
Exploitability
Impact
Vector string
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/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:X Attack Vector Network
Attack Complexity Low
Privileges Required None
User Interaction None
Scope X
Threat Intelligence
EPSS Exploit Probability
33.3% percentile
Exploit & Patch Status
No Known Exploit
No Patch Available
Weaknesses 1
CWE-476 NULL Pointer Dereference Memory Safety
Affected Products 4
| Vendor | Product | Version | Range |
|---|---|---|---|
| envoyproxy | envoy | * | <1.33.11 |
| envoyproxy | envoy | * | ≥1.34.0 – <1.34.9 |
| envoyproxy | envoy | * | ≥1.35.0 – <1.35.5 |
| envoyproxy | envoy | 1.36.0 | any |
References 1
- github.com https://github.com/envoyproxy/envoy/security/advisories/GHSA-pq33-4jxh-hgm3
Remediation
No remediation data recorded yet
Check vendor advisories and the NVD entry for patch availability.