Security readout for executives and security teams
Plain-English summary
Keycloak may trust attacker-supplied identity claims that should have required a valid signature. In affected OpenID Connect flows, this can let a remote, unauthenticated attacker alter authorization data. The primary risk is compromised integrity, not confidentiality or availability. A strict redirect URI allowlist reduces exposure but does not correct the policy bypass.
Executive priority
Schedule prompt remediation for affected identity infrastructure, especially regulated FAPI deployments or externally accessible authorization services. Although rated medium and requiring high complexity, successful abuse could undermine authorization decisions. Treat the redirect allowlist only as temporary risk reduction and confirm package-level remediation through the relevant Red Hat advisory.
Technical view
JWE request-object handling may accept decrypted raw JSON as unsigned claims despite a configured signature requirement. This CWE-347 flaw violates OIDC Core and FAPI signing expectations. CVSS 3.1 is 5.9: network-accessible, unauthenticated, high complexity, with high integrity impact and no stated confidentiality or availability impact.
Likely exposure
Exposure requires an affected Red Hat build of Keycloak and OIDC clients accepting JWE-encrypted request objects under a signature policy. Listed affected packages span Red Hat build of Keycloak 26.4 and 26.6. Package-specific versions differ, so verify installed RPM and operator bundle versions against each applicable Red Hat erratum.
Exploitation context
The flaw is remotely reachable without privileges or user interaction, but exploitation complexity is rated high. The supplied record is not in CISA KEV, and the sources provide no evidence of active exploitation or public weaponization. Impact depends on successfully injecting unauthorized claims into a vulnerable authorization flow.
Researcher notes
The critical distinction is between encrypted content and authenticated content: JWE decryption alone does not satisfy a required signature policy. Testing should focus on policy enforcement after decryption without developing offensive payloads. The source bundle lists package-specific affected states and unaffected product releases; consult the matching RHSA for authoritative upgrade boundaries.
Mitigation direction
- Apply the corrected Red Hat packages identified by the erratum matching your installed Keycloak package and release.
- Maintain strict redirect URI allowlists as a compensating control, not as a substitute for updating.
- Review vendor guidance before changing OIDC request-object or signature-policy settings.
- Prioritize internet-facing identity services and deployments supporting JWE-encrypted request objects.
Validation and detection
- Inventory Keycloak server, operator, and operator-bundle package versions separately.
- Compare installed package versions with the affected and corrected builds in the applicable Red Hat erratum.
- Confirm whether clients submit JWE-encrypted request objects and require signed request claims.
- Verify redirect URI allowlists contain only explicitly approved destinations.
- After updating, confirm unsigned decrypted JSON claims are rejected when signature policy requires signing.
Public sources used
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
Conservative CVE-to-ATT&CK context
These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.
ATT&CK lookup starting points
Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.
CWE-347: Exact CWE lookup
Use the exact CWE identifier as the starting point before reviewing related ATT&CK behavior. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.
Open ATT&CK lookupCVE-2026-9793 mapping review
Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.
Open ATT&CK lookup- Severity
- Medium
- CVSS
- 5.9 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N
CNA and ADP enrichment extracted from CVE v5
These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.
SSVC decision data
CVSS vector scores
1 official scoreWe collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N2.23.6redhatVulnerability scoring details
Base CVSS 3.1 score
5.9MediumVector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N
Vulnerability timeline
Timeline events are normalized from CVE metadata, CNA source timelines, ADP timelines, and KEV metadata when present.
- Source timelineredhat
Reported to Red Hat.
- CVE reservedCVE Program
The CVE ID was reserved by the assigning CNA.
- Source timelineredhat
Made public.
- CVE publishedCVE Program
The CVE record was published.
- CVE updatedCVE Program
The CVE record metadata indicates this as the latest update time.
ADP provider summaries
Source materials
- CVE List V5 sourceCVE List V5
- RHSA-2026:50846CVE reference, redhat · vendor-advisory, x_refsource_REDHAT
- RHSA-2026:50847CVE reference, redhat · vendor-advisory, x_refsource_REDHAT
- RHSA-2026:50848CVE reference, redhat · vendor-advisory, x_refsource_REDHAT
- RHSA-2026:50849CVE reference, redhat · vendor-advisory, x_refsource_REDHAT
- https://access.redhat.com/security/cve/CVE-2026-9793CVE reference, redhat · vdb-entry, x_refsource_REDHAT
- RHBZ#2482460CVE reference, redhat · issue-tracking, x_refsource_REDHAT
Products and packages named in the record
CWE details
CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.
Improper Verification of Cryptographic Signature
Improper Verification of Cryptographic Signature represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.