CVE-2026-33592
CVE-2026-33592 · FindServers Memory Exhaustion in open62541
This page contains facts from public vulnerability sources. Check the original advisory before updating.
An unauthenticated remote attacker can exhaust server memory via the FindServers Discovery Service in open62541. The serverUris field of FindServersRequest is not validated for length or array size. An attacker can declare an arbitrarily large string (up to ~3.9 GB) delivered across intermediate chunks without ever sending the final chunk. The server buffers all chunks in RAM indefinitely until the SecureChannel times out. The attack is pre-session and bypasses all encryption configuration. The issue affects open62541: from 1.4.0 through 1.4.16, from 1.5.0 through 1.5.4, master.
CVSS 7.5 · High · EPSS 0.5%
- Published
- Updated
Stack: system
Affected products and versions
open62541
- Versions
- ≥ 1.4.0, ≤ 1.4.16: Affected (semver)
- ≥ 1.5.0, ≤ 1.5.4: Affected (semver)
- master: Affected (custom)
No fix published
open62541 Debian:13
- Versions
- 1.4.11.1-1
- 1.4.18-1
- Affected ranges
- ECOSYSTEM: (−∞, +∞)
No fix published
open62541 Debian:14
- Versions
- 1.4.11.1-1
- 1.4.18-1
- Affected ranges
- ECOSYSTEM: (−∞, +∞)
No fix published
open62541 Ubuntu:25.10
- Versions
- 1.4.6-1
- 1.4.11.1-1
- Affected ranges
- ECOSYSTEM: (−∞, +∞)
No fix published
open62541 Ubuntu:26.10
- Versions
- 1.4.11.1-1build1
- 1.4.18-1
- Affected ranges
- ECOSYSTEM: (−∞, +∞)
No fix published
open62541 Ubuntu:26.04:LTS
- Versions
- 1.4.11.1-1
- 1.4.11.1-1build1
- Affected ranges
- ECOSYSTEM: (−∞, +∞)
No fix published