CVE-2026-47207: CWE-416: Use After Free in envoyproxy envoy
Envoy versions from 1.34.0 up to but not including 1.35.13, 1.36.9, 1.37.5, and 1.38.3 contain a use-after-free vulnerability triggered by specially crafted gRPC messages from an ext_proc server. This causes Envoy to crash due to improper handling of multiple ProcessingResponse messages in a single gRPC message. The vulnerability is fixed in versions 1.35.13, 1.36.9, 1.37.5, and 1.38.3.
AI Analysis
Technical Summary
A use-after-free vulnerability (CWE-416) exists in Envoy proxy when processing a single gRPC message containing multiple specially crafted ProcessingResponse messages from an ext_proc server. If the first response in the batch causes the gRPC stream object to be destroyed, Envoy attempts to access freed memory when processing subsequent responses, leading to a crash. This affects Envoy versions starting from 1.34.0 up to but not including the fixed versions 1.35.13, 1.36.9, 1.37.5, and 1.38.3.
Potential Impact
Successful exploitation causes a denial of service by crashing the Envoy proxy. There is no indication of confidentiality or integrity impact. The vulnerability requires at least low privileges (PR:L) and no user interaction. The attack vector is network-based (AV:N).
Mitigation Recommendations
Fixed versions are 1.35.13, 1.36.9, 1.37.5, and 1.38.3. Users should upgrade to one of these versions to remediate the vulnerability. Patch status is not explicitly confirmed in the vendor advisory, but the description states these versions contain the fix. No other mitigation or workaround is provided.
CVE-2026-47207: CWE-416: Use After Free in envoyproxy envoy
Description
Envoy versions from 1.34.0 up to but not including 1.35.13, 1.36.9, 1.37.5, and 1.38.3 contain a use-after-free vulnerability triggered by specially crafted gRPC messages from an ext_proc server. This causes Envoy to crash due to improper handling of multiple ProcessingResponse messages in a single gRPC message. The vulnerability is fixed in versions 1.35.13, 1.36.9, 1.37.5, and 1.38.3.
CVSS v3.1
Score 6.5medium
Affected software
pkg:github/envoyproxy/envoyRun on your own infrastructure? Check whether these packages are installed with threat-finder — our free open-source scanner.
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
A use-after-free vulnerability (CWE-416) exists in Envoy proxy when processing a single gRPC message containing multiple specially crafted ProcessingResponse messages from an ext_proc server. If the first response in the batch causes the gRPC stream object to be destroyed, Envoy attempts to access freed memory when processing subsequent responses, leading to a crash. This affects Envoy versions starting from 1.34.0 up to but not including the fixed versions 1.35.13, 1.36.9, 1.37.5, and 1.38.3.
Potential Impact
Successful exploitation causes a denial of service by crashing the Envoy proxy. There is no indication of confidentiality or integrity impact. The vulnerability requires at least low privileges (PR:L) and no user interaction. The attack vector is network-based (AV:N).
Mitigation Recommendations
Fixed versions are 1.35.13, 1.36.9, 1.37.5, and 1.38.3. Users should upgrade to one of these versions to remediate the vulnerability. Patch status is not explicitly confirmed in the vendor advisory, but the description states these versions contain the fix. No other mitigation or workaround is provided.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- GitHub_M
- Date Reserved
- 2026-05-18T22:25:21.257Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 6a3ec10ed9e07477746fae12
Added to database: 06/26/2026, 18:12:30 UTC
Last enriched: 06/26/2026, 18:23:20 UTC
Last updated: 06/26/2026, 18:23:40 UTC
Views: 2
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