CVE-2026-117470
WebAuthn assertion replay permits second-factor bypass in Psono Server
CVSS Score
6.5
EPSS Score
0.0%
EPSS Percentile
0th
Psono Server CE & EE versions 3.1.0 through 7.2.3 did not consume a stored WebAuthn challenge after assertion verification. An unauthenticated remote attacker who possessed the user's password and one captured valid WebAuthn assertion could replay that assertion with separate login tokens while the stored challenge remained unchanged, bypassing the WebAuthn second factor. The attack required capture of a valid assertion and did not itself disclose plaintext secrets.
| CWE | CWE-294 |
| Vendor | esaqa gmbh |
| Product | psono |
| Published | Oct 27, 2026 |
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CVSS v3 Breakdown
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:H/A:N Attack Vector
Network
Attack Complexity
High
Privileges Required
None
User Interaction
None
Scope
Unchanged
Confidentiality
Low
Integrity
High
Availability
None
Affected Versions
esaqa GmbH / Psono
3.1.0 < 7.2.4
References
gitlab.com: https://gitlab.com/esaqa/esaqa/security-advisories/-/blob/master/advisories/CVE-2026-117470.md gitlab.com: https://gitlab.com/esaqa/psono/psono-server/-/blob/v7.2.3/psono/restapi/serializers/webauthn_verify.py gitlab.com: https://gitlab.com/esaqa/psono/psono-server/-/commit/9c9a7f1701535df63370340dcc80210737dc495d gitlab.com: https://gitlab.com/esaqa/psono/psono-server/-/releases/v7.2.4 gitlab.com: https://gitlab.com/esaqa/psono/psono-server
Credits
Ryan Chaplin