In Eclipse Milo versions 1.0.0 through 1.1.4, monitored-item quota accounting is not exception-safe: if item creation fails with an unchecked error, the server-global reservation is not restored. Deeply nested PubSub ExtensionObjects in a `CreateMonitoredItems` event filter can trigger a `StackOverflowError` during decoding, allowing an unauthenticated remote client to exhaust a finite global monitored-item quota and prevent all clients from creating new monitored items until restart. Existing monitored items and other server functions remain unaffected.
https://gitlab.eclipse.org/security/vulnerability-reports/-/work_items/598
https://gitlab.eclipse.org/security/cve-assignment/-/work_items/182
https://github.com/eclipse-milo/milo/commit/5f3f6da2a5ea80682e1da7c58f7a1870b09d2b43
https://github.com/eclipse-milo/milo/commit/587e35669f519b2d7f6d850a5f86ee5a76c3a2c5
Published: 2026-08-04
Updated: 2026-08-05
Base Score: 7.8
Vector: CVSS2#AV:N/AC:L/Au:N/C:N/I:N/A:C
Severity: High
Base Score: 7.5
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Severity: High
Base Score: 6.9
Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N
Severity: Medium
EPSS: 0.00301