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
eclipse: milo
References3
- gitlab.eclipse.org/security/cve-assignment/-/work_items/183 Issue TrackingPatchVendor Advisory
- gitlab.eclipse.org/security/vulnerability-reports/-/work_items/… Issue TrackingVendor Advisory
- github.com/eclipse-milo/milo/commit/db59fae993a3a1bc66fffc8a279… Patch
Metrics
- CVSS 3.1
-
7.4
HIGH
Score source: NVD
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N - CVSS 4.0
-
9.1
CRITICAL
Score source: CNA
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - EPSS — exploit probability
- 1% percentile: 47 · as of 13 November 2026
- CWE
- CWE-204
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