Advisory details:
github_osv / GHSA-rr5q-3xwr-f323
| Advisory ID | github_osv/GHSA-rr5q-3xwr-f323 |
| Aliases |
CVE-2026-9704
|
| Summary | Keycloak Vulnerable to Improper Validation of Specified Quantity in Input A flaw was found in Keycloak. An authenticated user with low privileges can exploit this vulnerability by sending an oversized subject_token JSON Web Token (JWT) to the TokenEndpoint. When the token exceeds a 4000-character limit, it is silently dropped, causing the system to fall back to client credentials. This allows the user to gain the permissions of the client's service account, leading to privilege escalation. |
| Status | Published |
| Exploitability | 0.5 |
| Weighted Severity | 6.1 |
| Risk | 3.0 |
| Affected and Fixed Packages | Package Details |
| Introduced and Fixed Package Commit Patches | Package Commit Patches Details |
| System | Score | Found at |
|---|---|---|
| cvssv3.1 | 6.8 | https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/05/GHSA-rr5q-3xwr-f323/GHSA-rr5q-3xwr-f323.json |
| generic_textual | MODERATE |
| Reference id | Reference type | URL |
|---|---|---|
| https://access.redhat.com/errata/RHSA-2026:30049 | ||
| https://access.redhat.com/errata/RHSA-2026:30050 | ||
| https://github.com/keycloak/keycloak | ||
| https://github.com/keycloak/keycloak/commit/f1e5b7776c42938d0782fd5846346b8f75c815e6 | ||
| https://github.com/keycloak/keycloak/issues/49435 | ||
| https://github.com/keycloak/keycloak/pull/49472 | ||
| CVE-2026-9704 | Advisory | https://access.redhat.com/security/cve/CVE-2026-9704 |
| CVE-2026-9704 | https://nvd.nist.gov/vuln/detail/CVE-2026-9704 | |
| RHSA-2026:25097 | Advisory | https://access.redhat.com/errata/RHSA-2026:25097 |
| RHSA-2026:25098 | Advisory | https://access.redhat.com/errata/RHSA-2026:25098 |
| show_bug.cgi?id=2481877 | Bug | https://bugzilla.redhat.com/show_bug.cgi?id=2481877 |
No EPSS data available for this advisory.
| Patch URL | |
|---|---|
| There are no known patches. | |
| Attack Vector (AV) | Attack Complexity (AC) | Privileges Required (PR) | User Interaction (UI) | Scope (S) | Confidentiality Impact (C) | Integrity Impact (I) | Availability Impact (A) |
|---|---|---|---|---|---|---|---|
network adjacent_network local physical |
low high |
none low high |
none required |
unchanged changed |
high low none |
high low none |
high low none |
Vector: SSVCv2/E:N/A:N/T:T/P:M/B:A/M:M/D:T/2026-05-27T15:29:17Z/
Decision: Track
Source URL: https://github.com/cisagov/vulnrichment/blob/develop/2026/9xxx/CVE-2026-9704.json
Source Advisory: vulnrichment/CVE-2026-9704
[{'Exploitation': 'none'},
{'Automatable': 'no'},
{'Technical Impact': 'total'},
{'Mission Prevalence': 'minimal'},
{'Public Well-being Impact': 'material'},
{'Mission & Well-being': 'medium'}]