CVE-2026-0976 (GCVE-0-2026-0976)
Vulnerability from cvelistv5
Published
2026-01-15 12:06
Modified
2026-01-15 14:45
CWE
  • CWE-20 - Improper Input Validation
Summary
A flaw was found in Keycloak. This improper input validation vulnerability occurs because Keycloak accepts RFC-compliant matrix parameters in URL path segments, while common reverse proxy configurations may ignore or mishandle them. A remote attacker can craft requests to mask path segments, potentially bypassing proxy-level path filtering. This could expose administrative or sensitive endpoints that operators believe are not externally reachable.
References
Show details on NVD website


{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-0976",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-01-15T14:44:09.361820Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-01-15T14:45:41.540Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
          "cpes": [
            "cpe:/a:redhat:build_keycloak:"
          ],
          "defaultStatus": "affected",
          "packageName": "org.keycloak/keycloak-quarkus-server",
          "product": "Red Hat Build of Keycloak",
          "vendor": "Red Hat"
        },
        {
          "collectionURL": "https://access.redhat.com/jbossnetwork/restricted/listSoftware.html",
          "cpes": [
            "cpe:/a:redhat:jboss_enterprise_application_platform:8"
          ],
          "defaultStatus": "affected",
          "packageName": "keycloak-quarkus-server",
          "product": "Red Hat JBoss Enterprise Application Platform 8",
          "vendor": "Red Hat"
        },
        {
          "collectionURL": "https://access.redhat.com/jbossnetwork/restricted/listSoftware.html",
          "cpes": [
            "cpe:/a:redhat:jboss_enterprise_application_platform:8"
          ],
          "defaultStatus": "affected",
          "packageName": "keycloak-quarkus-server-app",
          "product": "Red Hat JBoss Enterprise Application Platform 8",
          "vendor": "Red Hat"
        },
        {
          "collectionURL": "https://access.redhat.com/jbossnetwork/restricted/listSoftware.html",
          "cpes": [
            "cpe:/a:redhat:jboss_enterprise_application_platform:8"
          ],
          "defaultStatus": "affected",
          "packageName": "keycloak-quarkus-server-deployment",
          "product": "Red Hat JBoss Enterprise Application Platform 8",
          "vendor": "Red Hat"
        },
        {
          "collectionURL": "https://access.redhat.com/jbossnetwork/restricted/listSoftware.html",
          "cpes": [
            "cpe:/a:redhat:jbosseapxp"
          ],
          "defaultStatus": "affected",
          "packageName": "keycloak-quarkus-server",
          "product": "Red Hat JBoss Enterprise Application Platform Expansion Pack",
          "vendor": "Red Hat"
        },
        {
          "collectionURL": "https://access.redhat.com/jbossnetwork/restricted/listSoftware.html",
          "cpes": [
            "cpe:/a:redhat:jbosseapxp"
          ],
          "defaultStatus": "affected",
          "packageName": "keycloak-quarkus-server-app",
          "product": "Red Hat JBoss Enterprise Application Platform Expansion Pack",
          "vendor": "Red Hat"
        },
        {
          "collectionURL": "https://access.redhat.com/jbossnetwork/restricted/listSoftware.html",
          "cpes": [
            "cpe:/a:redhat:jbosseapxp"
          ],
          "defaultStatus": "affected",
          "packageName": "keycloak-quarkus-server-deployment",
          "product": "Red Hat JBoss Enterprise Application Platform Expansion Pack",
          "vendor": "Red Hat"
        }
      ],
      "credits": [
        {
          "lang": "en",
          "value": "Red Hat would like to thank Alexander Schwartz (RedHat) for reporting this issue."
        }
      ],
      "datePublic": "2026-01-15T00:00:00.000Z",
      "descriptions": [
        {
          "lang": "en",
          "value": "A flaw was found in Keycloak. This improper input validation vulnerability occurs because Keycloak accepts RFC-compliant matrix parameters in URL path segments, while common reverse proxy configurations may ignore or mishandle them. A remote attacker can craft requests to mask path segments, potentially bypassing proxy-level path filtering. This could expose administrative or sensitive endpoints that operators believe are not externally reachable."
        }
      ],
      "metrics": [
        {
          "other": {
            "content": {
              "namespace": "https://access.redhat.com/security/updates/classification/",
              "value": "Low"
            },
            "type": "Red Hat severity rating"
          }
        },
        {
          "cvssV3_1": {
            "attackComplexity": "HIGH",
            "attackVector": "NETWORK",
            "availabilityImpact": "NONE",
            "baseScore": 3.7,
            "baseSeverity": "LOW",
            "confidentialityImpact": "LOW",
            "integrityImpact": "NONE",
            "privilegesRequired": "NONE",
            "scope": "UNCHANGED",
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N",
            "version": "3.1"
          },
          "format": "CVSS"
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-20",
              "description": "Improper Input Validation",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-01-15T12:06:21.251Z",
        "orgId": "53f830b8-0a3f-465b-8143-3b8a9948e749",
        "shortName": "redhat"
      },
      "references": [
        {
          "tags": [
            "vdb-entry",
            "x_refsource_REDHAT"
          ],
          "url": "https://access.redhat.com/security/cve/CVE-2026-0976"
        },
        {
          "name": "RHBZ#2429869",
          "tags": [
            "issue-tracking",
            "x_refsource_REDHAT"
          ],
          "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2429869"
        }
      ],
      "timeline": [
        {
          "lang": "en",
          "time": "2026-01-15T06:43:23.112Z",
          "value": "Reported to Red Hat."
        },
        {
          "lang": "en",
          "time": "2026-01-15T00:00:00.000Z",
          "value": "Made public."
        }
      ],
      "title": "Org.keycloak/keycloak-quarkus-server: keycloak: proxy bypass due to improper handling of matrix parameters in url paths",
      "workarounds": [
        {
          "lang": "en",
          "value": "To mitigate this issue, ensure that all administrative and sensitive endpoints within Keycloak are adequately protected by robust authentication and authorization policies, independent of any reverse proxy path filtering. Operators should review Keycloak\u0027s internal access controls to confirm that access to these endpoints is restricted to authorized users and roles."
        }
      ],
      "x_generator": {
        "engine": "cvelib 1.8.0"
      },
      "x_redhatCweChain": "CWE-20: Improper Input Validation"
    }
  },
  "cveMetadata": {
    "assignerOrgId": "53f830b8-0a3f-465b-8143-3b8a9948e749",
    "assignerShortName": "redhat",
    "cveId": "CVE-2026-0976",
    "datePublished": "2026-01-15T12:06:21.251Z",
    "dateReserved": "2026-01-15T06:43:41.332Z",
    "dateUpdated": "2026-01-15T14:45:41.540Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "vulnerability-lookup:meta": {
    "vulnrichment": {
      "containers": "{\"adp\": [{\"title\": \"CISA ADP Vulnrichment\", \"metrics\": [{\"other\": {\"type\": \"ssvc\", \"content\": {\"id\": \"CVE-2026-0976\", \"role\": \"CISA Coordinator\", \"options\": [{\"Exploitation\": \"none\"}, {\"Automatable\": \"no\"}, {\"Technical Impact\": \"partial\"}], \"version\": \"2.0.3\", \"timestamp\": \"2026-01-15T14:44:09.361820Z\"}}}], \"providerMetadata\": {\"orgId\": \"134c704f-9b21-4f2e-91b3-4a467353bcc0\", \"shortName\": \"CISA-ADP\", \"dateUpdated\": \"2026-01-15T14:45:37.752Z\"}}], \"cna\": {\"title\": \"Org.keycloak/keycloak-quarkus-server: keycloak: proxy bypass due to improper handling of matrix parameters in url paths\", \"credits\": [{\"lang\": \"en\", \"value\": \"Red Hat would like to thank Alexander Schwartz (RedHat) for reporting this issue.\"}], \"metrics\": [{\"other\": {\"type\": \"Red Hat severity rating\", \"content\": {\"value\": \"Low\", \"namespace\": \"https://access.redhat.com/security/updates/classification/\"}}}, {\"format\": \"CVSS\", \"cvssV3_1\": {\"scope\": \"UNCHANGED\", \"version\": \"3.1\", \"baseScore\": 3.7, \"attackVector\": \"NETWORK\", \"baseSeverity\": \"LOW\", \"vectorString\": \"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N\", \"integrityImpact\": \"NONE\", \"userInteraction\": \"NONE\", \"attackComplexity\": \"HIGH\", \"availabilityImpact\": \"NONE\", \"privilegesRequired\": \"NONE\", \"confidentialityImpact\": \"LOW\"}}], \"affected\": [{\"cpes\": [\"cpe:/a:redhat:build_keycloak:\"], \"vendor\": \"Red Hat\", \"product\": \"Red Hat Build of Keycloak\", \"packageName\": \"org.keycloak/keycloak-quarkus-server\", \"collectionURL\": \"https://access.redhat.com/downloads/content/package-browser/\", \"defaultStatus\": \"affected\"}, {\"cpes\": [\"cpe:/a:redhat:jboss_enterprise_application_platform:8\"], \"vendor\": \"Red Hat\", \"product\": \"Red Hat JBoss Enterprise Application Platform 8\", \"packageName\": \"keycloak-quarkus-server\", \"collectionURL\": \"https://access.redhat.com/jbossnetwork/restricted/listSoftware.html\", \"defaultStatus\": \"affected\"}, {\"cpes\": [\"cpe:/a:redhat:jboss_enterprise_application_platform:8\"], \"vendor\": \"Red Hat\", \"product\": \"Red Hat JBoss Enterprise Application Platform 8\", \"packageName\": \"keycloak-quarkus-server-app\", \"collectionURL\": \"https://access.redhat.com/jbossnetwork/restricted/listSoftware.html\", \"defaultStatus\": \"affected\"}, {\"cpes\": [\"cpe:/a:redhat:jboss_enterprise_application_platform:8\"], \"vendor\": \"Red Hat\", \"product\": \"Red Hat JBoss Enterprise Application Platform 8\", \"packageName\": \"keycloak-quarkus-server-deployment\", \"collectionURL\": \"https://access.redhat.com/jbossnetwork/restricted/listSoftware.html\", \"defaultStatus\": \"affected\"}, {\"cpes\": [\"cpe:/a:redhat:jbosseapxp\"], \"vendor\": \"Red Hat\", \"product\": \"Red Hat JBoss Enterprise Application Platform Expansion Pack\", \"packageName\": \"keycloak-quarkus-server\", \"collectionURL\": \"https://access.redhat.com/jbossnetwork/restricted/listSoftware.html\", \"defaultStatus\": \"affected\"}, {\"cpes\": [\"cpe:/a:redhat:jbosseapxp\"], \"vendor\": \"Red Hat\", \"product\": \"Red Hat JBoss Enterprise Application Platform Expansion Pack\", \"packageName\": \"keycloak-quarkus-server-app\", \"collectionURL\": \"https://access.redhat.com/jbossnetwork/restricted/listSoftware.html\", \"defaultStatus\": \"affected\"}, {\"cpes\": [\"cpe:/a:redhat:jbosseapxp\"], \"vendor\": \"Red Hat\", \"product\": \"Red Hat JBoss Enterprise Application Platform Expansion Pack\", \"packageName\": \"keycloak-quarkus-server-deployment\", \"collectionURL\": \"https://access.redhat.com/jbossnetwork/restricted/listSoftware.html\", \"defaultStatus\": \"affected\"}], \"timeline\": [{\"lang\": \"en\", \"time\": \"2026-01-15T06:43:23.112Z\", \"value\": \"Reported to Red Hat.\"}, {\"lang\": \"en\", \"time\": \"2026-01-15T00:00:00.000Z\", \"value\": \"Made public.\"}], \"datePublic\": \"2026-01-15T00:00:00.000Z\", \"references\": [{\"url\": \"https://access.redhat.com/security/cve/CVE-2026-0976\", \"tags\": [\"vdb-entry\", \"x_refsource_REDHAT\"]}, {\"url\": \"https://bugzilla.redhat.com/show_bug.cgi?id=2429869\", \"name\": \"RHBZ#2429869\", \"tags\": [\"issue-tracking\", \"x_refsource_REDHAT\"]}], \"workarounds\": [{\"lang\": \"en\", \"value\": \"To mitigate this issue, ensure that all administrative and sensitive endpoints within Keycloak are adequately protected by robust authentication and authorization policies, independent of any reverse proxy path filtering. Operators should review Keycloak\u0027s internal access controls to confirm that access to these endpoints is restricted to authorized users and roles.\"}], \"x_generator\": {\"engine\": \"cvelib 1.8.0\"}, \"descriptions\": [{\"lang\": \"en\", \"value\": \"A flaw was found in Keycloak. This improper input validation vulnerability occurs because Keycloak accepts RFC-compliant matrix parameters in URL path segments, while common reverse proxy configurations may ignore or mishandle them. A remote attacker can craft requests to mask path segments, potentially bypassing proxy-level path filtering. This could expose administrative or sensitive endpoints that operators believe are not externally reachable.\"}], \"problemTypes\": [{\"descriptions\": [{\"lang\": \"en\", \"type\": \"CWE\", \"cweId\": \"CWE-20\", \"description\": \"Improper Input Validation\"}]}], \"providerMetadata\": {\"orgId\": \"53f830b8-0a3f-465b-8143-3b8a9948e749\", \"shortName\": \"redhat\", \"dateUpdated\": \"2026-01-15T12:06:21.251Z\"}, \"x_redhatCweChain\": \"CWE-20: Improper Input Validation\"}}",
      "cveMetadata": "{\"cveId\": \"CVE-2026-0976\", \"state\": \"PUBLISHED\", \"dateUpdated\": \"2026-01-15T14:45:41.540Z\", \"dateReserved\": \"2026-01-15T06:43:41.332Z\", \"assignerOrgId\": \"53f830b8-0a3f-465b-8143-3b8a9948e749\", \"datePublished\": \"2026-01-15T12:06:21.251Z\", \"assignerShortName\": \"redhat\"}",
      "dataType": "CVE_RECORD",
      "dataVersion": "5.2"
    }
  }
}


Log in or create an account to share your comment.




Tags
Taxonomy of the tags.


Loading…

Loading…

Loading…

Sightings

Author Source Type Date

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or seen somewhere by the user.
  • Confirmed: The vulnerability is confirmed from an analyst perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: This vulnerability was exploited and seen by the user reporting the sighting.
  • Patched: This vulnerability was successfully patched by the user reporting the sighting.
  • Not exploited: This vulnerability was not exploited or seen by the user reporting the sighting.
  • Not confirmed: The user expresses doubt about the veracity of the vulnerability.
  • Not patched: This vulnerability was not successfully patched by the user reporting the sighting.


Loading…

Loading…