Memory Corruption Vulnerability in Zephyr HTTP Server's HTTP/2 Front-End
CVE-2026-82391

9.1CRITICAL

Key Information:

Vendor

Zephyrproject

Status
Zephyr
Vendor
CVE Published:
10 November 2026

What is CVE-2026-82391?

The vulnerability in Zephyr's HTTP/2 front-end affects the static file handling functionality. When an unauthenticated HTTP/2 GET request is made for any file under the web root, it improperly processes connection states, leading to potential remote memory corruption. This attack can exploit the fixed-size buffer within the server, allowing an attacker to manipulate the data and potentially execute arbitrary code or crash the server.

Affected Version(s)

zephyr 4.0.0 < 4.3.2

zephyr 4.4.0 < 4.5.0

References

https://github.com/zephyrproject-rtos/zephyr/commit/4e0a5...
patch
https://github.com/zephyrproject-rtos/zephyr/security/adv...

CVSS V3.1

Score:
9.1
Severity:
CRITICAL
Confidentiality:
None
Integrity:
High
Availability:
None
Attack Vector:
Network
Attack Complexity:
Low
Privileges Required:
None
User Interaction:
None
Scope:
Unchanged

Timeline

  • Vulnerability published

  • Vulnerability Reserved

.