CVE-2023-0657 | Keycloak: impersonation via logout token exchange

A flaw was found in Keycloak. This issue occurs due to improperly enforcing token types when validating signatures locally. This could allow an authenticated attacker to exchange a logout token for an access token and possibly gain access to data outside of enforced permissions.

Published: 2024-11-17 Last update: 2026-04-15 Assigner: [email protected] Source: [email protected]
NVD Status：Deferred，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2023-0657 is rated Low Risk (21.3/100): CVSS Low severity, with low exploitation likelihood (EPSS 0.30%). Monitor for updates and reassess as exploit intelligence or EPSS changes.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2023-0657

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-15 0.05% 0.30% +0.24%
2 2026-04-08 0.05% 0.05% +0.01%
3 2025-12-27 — 0.05% —

Full EPSS history (5 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2023-0657

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
3.4 3.1 LOW
CVSS:3.1/AV:A/AC:H/PR:L/UI:R/S:U/C:L/I:L/A:N Click to expand
Attack vector (AV:A)
Attacker has to be nearby on the network—same office, same link, that vibe—not the whole wide internet.
Attack complexity (AC:H)
Even with access, the exploit needs extra luck, timing, or a fussy environment to actually work.
Privileges required (PR:L)
A normal user session is enough; they don’t have to be admin.
User interaction (UI:R)
A real person has to do something—click, install, enable—otherwise it doesn’t land.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:L)
Some sensitive info could get out, but not a total data dump.
Integrity (I:L)
Attackers could change some data, but it’s limited—not everything goes.
Availability (A:N)
Service keeps running; no real outage angle.
 0.9 2.5 [email protected]

Weakness enumeration for CVE-2023-0657

GitHub Security Advisory for CVE-2023-0657

GHSA-7fpj-9hr8-28vh · Severity: low · Ecosystem: maven — Keycloak vulnerable to impersonation via logout token exchange

OS Trackers for CVE-2023-0657

vendor priority summary link
redhat low — https://access.redhat.com/security/cve/CVE-2023-0657

Affected software / configurations for CVE-2023-0657

Vendor Product Version Raw CPE
No affected products in dataset.

References for CVE-2023-0657

cvelogic Threat Intelligence