Description
In Eclipse Milo versions 0.6.0 through 1.1.4, username-token processing returns distinguishable errors for invalid RSA PKCS#1 v1.5 padding and other authentication failures, allowing an on-path attacker who captures a victim's `Basic128Rsa15`-encrypted username token to use repeated unauthenticated `ActivateSession` requests as a padding oracle, recover the victim's password, and authenticate with the recovered credentials.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| Eclipse Foundation | Eclipse Milo | 0.6.0 – ≤ 1.1.4 | — |
Advisories 1
- ICSA-26-288-01 Eclipse Foundation Eclipse Milo CISA ICS & IT advisories · Oct 15, 2026