GHSA-j97h-3f8r-mrjr

Suggest an improvement
Source
https://github.com/advisories/GHSA-j97h-3f8r-mrjr
Import Source
https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/11/GHSA-j97h-3f8r-mrjr/GHSA-j97h-3f8r-mrjr.json
JSON Data
https://api.osv.dev/v1/vulns/GHSA-j97h-3f8r-mrjr
Aliases
Published
2026-11-03T17:24:27Z
Modified
2026-11-03T17:55:47Z
Severity
  • 8.1 (High) CVSS_V3 - CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N CVSS Calculator
Summary
Keycloak has authentication bypass via jwt algorithm confusion
Details

Description

A flaw was found in Keycloak. This JWT algorithm confusion vulnerability in the JWT Authorization Grant flow allows an attacker with valid client credentials to bypass signature verification. By forging an assertion, the attacker can create unauthorized access tokens. This enables the attacker to impersonate any federated user linked to the affected Identity Provider, leading to unauthorized access and potential privilege escalation.

Database specific 
{
    "cwe_ids": [
        "CWE-347"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-11-03T17:24:27Z",
    "nvd_published_at": null,
    "severity": "HIGH"
}
References

Affected packages

Maven / org.keycloak:keycloak-services

Package

Name
org.keycloak:keycloak-services
View open source insights on deps.dev
Purl
pkg:maven/org.keycloak/keycloak-services

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0 Unknown introduced version / All previous versions are affected
Fixed
26.6.4

Affected versions

1.*
1.0-alpha-1
1.0-alpha-1-12062013
1.0-alpha-2
1.0-alpha-3
1.0-alpha-4
1.0-beta-1
1.0-beta-1-20150521
1.0-beta-1-20150523
1.0-beta-2
1.0-beta-3
1.0-beta-4
1.0-rc-1
1.0-rc-2
1.0-final
1.0.1.Final
1.0.2.Final
1.0.3.Final
1.0.4.Final
1.0.5.Final
1.1.0.Beta1
1.1.0.Beta2
1.1.0.Final
1.1.1.Final
1.2.0.Beta1
1.2.0.CR1
1.2.0.Final
1.3.0.Final
1.3.1.Final
1.4.0.Final
1.5.0-Final
1.5.0.Final
1.5.1.Final
1.6.0.Final
1.6.1.Final
1.7.0.CR1
1.7.0.Final
1.8.0.Alpha1
1.8.0.CR1
1.8.0.CR2
1.8.0.CR3
1.8.0.Final
1.8.1.Final
1.9.0.CR1
1.9.0.Final
1.9.1.Final
1.9.2.Final
1.9.3.Final
1.9.4.Final
1.9.5.Final
1.9.7.Final
1.9.8.Final
2.*
2.0.0.CR1
2.0.0.Final
2.1.0.CR1
2.1.0.Final
2.2.0.CR1
2.2.0.Final
2.2.1.Final
2.3.0.CR1
2.3.0.Final
2.4.0.CR1
2.4.0.Final
2.5.0.CR1
2.5.0.Final
2.5.1.Final
2.5.4.Final
2.5.5.Final
3.*
3.0.0.CR1
3.0.0.Final
3.1.0.CR1
3.1.0.Final
3.2.0.CR1
3.2.0.Final
3.2.1.Final
3.3.0.CR1
3.3.0.CR2
3.3.0.Final
3.4.0.CR1
3.4.0.Final
3.4.1.CR1
3.4.1.Final
3.4.2.Final
3.4.3.Final
4.*
4.0.0.Beta1
4.0.0.Beta2
4.0.0.Beta3
4.0.0.Final
4.1.0.Final
4.2.0.Final
4.2.1.Final
4.3.0.Final
4.4.0.Final
4.5.0.Final
4.6.0.Final
4.7.0.Final
4.8.0.Final
4.8.1.Final
4.8.2.Final
4.8.3.Final
5.*
5.0.0
6.*
6.0.0
6.0.1
7.*
7.0.0
7.0.1
8.*
8.0.0
8.0.1
8.0.2
9.*
9.0.0
9.0.2
9.0.3
10.*
10.0.0
10.0.1
10.0.2
11.*
11.0.0
11.0.1
11.0.2
11.0.3
12.*
12.0.0
12.0.1
12.0.2
12.0.3
12.0.4
13.*
13.0.0
13.0.1
14.*
14.0.0
15.*
15.0.0
15.0.1
15.0.2
15.1.0
15.1.1
16.*
16.0.0
16.1.0
16.1.1
17.*
17.0.0
17.0.1
18.*
18.0.0
18.0.1
18.0.2
19.*
19.0.0
19.0.1
19.0.2
19.0.3
20.*
20.0.0
20.0.1
20.0.2
20.0.3
20.0.4
20.0.5
21.*
21.0.0
21.0.1
21.0.2
21.1.0
21.1.1
21.1.2
22.*
22.0.0
22.0.1
22.0.2
22.0.3
22.0.4
22.0.5
23.*
23.0.0
23.0.1
23.0.2
23.0.3
23.0.4
23.0.5
23.0.6
23.0.7
24.*
24.0.0
24.0.1
24.0.2
24.0.3
24.0.4
24.0.5
25.*
25.0.0
25.0.1
25.0.2
25.0.3
25.0.4
25.0.5
25.0.6
26.*
26.0.0
26.0.1
26.0.2
26.0.3
26.0.4
26.0.5
26.0.6
26.0.7
26.0.8
26.1.0
26.1.1
26.1.2
26.1.3
26.1.4
26.1.5
26.2.0
26.2.1
26.2.2
26.2.3
26.2.4
26.2.5
26.3.0
26.3.1
26.3.2
26.3.3
26.3.4
26.3.5
26.4.0
26.4.1
26.4.2
26.4.3
26.4.4
26.4.5
26.4.6
26.4.7
26.5.0
26.5.1
26.5.2
26.5.3
26.5.4
26.5.5
26.5.6
26.5.7
26.6.0
26.6.1
26.6.2
26.6.3

Database specific

source 
"https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/11/GHSA-j97h-3f8r-mrjr/GHSA-j97h-3f8r-mrjr.json"