Istio JWKS resolver to prevent private key material from being exposed when JWKS fetch fails.

{
  "id": "88be7b6e6cef1a82031f0581237258ca2552f0a205d61c8bbdb4100434749251",
  "url": "https://osv.dev/vulnerability/CVE-2026-31837",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "Istio JWKS resolver to prevent private key material from being exposed when JWKS fetch fails.",
    "summary": "Istio is an open platform to connect, manage, and secure microservices. Prior to 1.29.1, 1.28.5, and 1.27.8, a user of Istio is impacted if the JWKS resolver becomes unavailable or the fetch fails, exposing hardcoded defaults regardless of use of the RequestAuthentication resource. This vulnerability is fixed in 1.29.1, 1.28.5, and 1.27.8.",
    "evidence": "osv:CVE-2026-31837",
    "products": [],
    "severity": "high",
    "structured": {
      "id": "CVE-2026-31837",
      "aliases": [
        "CVE-2026-31837",
        "GHSA-v75c-crr9-733c"
      ],
      "metrics": [
        {
          "type": "CVSS_V4",
          "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N"
        }
      ],
      "affected": [
        {
          "ranges": [
            {
              "repo": "https://github.com/istio/istio",
              "type": "GIT",
              "events": [
                {
                  "introduced": "0"
                },
                {
                  "fixed": "4aee98e195c1af3f5e9385c637050db22d8c41d8"
                },
                {
                  "introduced": "b8d1df54465060428c2a2a38286e360beb85fb31"
                },
                {
                  "fixed": "7da6662175184479cb9281f3d814d6994bf1009f"
                },
                {
                  "introduced": "2300e2458ab713c2c514a58da1ea8b03343ada7e"
                },
                {
                  "fixed": "6991a379e1fcfbe21e64da2eda5d56624a5547b4"
                }
              ],
              "database_specific": {
                "extracted_events": [
                  {
                    "cpe": "cpe:2.3:a:istio:istio:*:*:*:*:*:*:*:*",
                    "range": [
                      {
                        "introduced": "0"
                      },
                      {
                        "fixed": "1.27.8"
                      }
                    ],
                    "source": "CPE_RANGE"
                  },
                  {
                    "cpe": "cpe:2.3:a:istio:istio:*:*:*:*:*:*:*:*",
                    "range": [
                      {
                        "introduced": "1.28.0"
                      },
                      {
                        "fixed": "1.28.5"
                      }
                    ],
                    "source": "CPE_RANGE"
                  },
                  {
                    "cpe": "cpe:2.3:a:istio:istio:*:*:*:*:*:*:*:*",
                    "range": [
                      {
                        "introduced": "1.29.0"
                      },
                      {
                        "fixed": "1.29.1"
                      }
                    ],
                    "source": "CPE_RANGE"
                  }
                ]
              }
            }
          ],
          "versions": [
            "1.29.0-rc.3",
            "1.29.0",
            "1.28.4",
            "1.27.7",
            "1.27.6",
            "1.28.3",
            "1.28.2",
            "1.27.5",
            "1.28.0-rc.1",
            "1.28.0",
            "1.27.3",
            "1.27.2",
            "1.27.1",
            "1.27.0",
            "1.27.0-rc.0",
            "1.27.0-beta.0",
            "1.26.0-alpha.0",
            "1.25.0-alpha.0",
            "1.24.0-alpha.0",
            "1.23.0-alpha.0",
            "1.22.0-alpha.1",
            "1.19.0-alpha.1",
            "1.19.0-alpha.0",
            "1.18.0-alpha.0",
            "1.12.0-alpha.5",
            "1.12.0-alpha.1",
            "1.12.0-alpha.0",
            "1.7.0-alpha.0",
            "1.6.0-alpha.2",
            "1.6.0-alpha.1",
            "1.6.0-alpha.0",
            "1.5.0-beta.2",
            "1.5.0-beta.1",
            "1.5.0-alpha.0",
            "1.2.0-rc.3",
            "1.2.0-rc.0",
            "1.1.0-snapshot.2",
            "1.1.0.snapshot.1",
            "1.1.0.snapshot.0",
            "1.0.0-snapshot.0",
            "0.6.0",
            "0.5.0",
            "0.3.0"
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-31837.json"
          }
        }
      ],
      "modified": "2026-10-28T02:30:23.521415505Z",
      "provider": "osv",
      "references": [
        "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-31837.json",
        "https://access.redhat.com/errata/RHSA-2026:10184",
        "https://access.redhat.com/errata/RHSA-2026:5948",
        "https://access.redhat.com/errata/RHSA-2026:5950",
        "https://access.redhat.com/errata/RHSA-2026:5952",
        "https://access.redhat.com/security/cve/CVE-2026-31837",
        "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/31xxx/CVE-2026-31837.json",
        "https://github.com/istio/istio/security/advisories/GHSA-v75c-crr9-733c",
        "https://nvd.nist.gov/vuln/detail/CVE-2026-31837",
        "https://bugzilla.redhat.com/show_bug.cgi?id=2446344"
      ],
      "provider_metadata": {
        "cwe_ids": [
          "CWE-200"
        ],
        "cna_assigner": "GitHub_M",
        "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/31xxx/CVE-2026-31837.json"
      }
    },
    "related_cves": [
      {
        "value": "CVE-2026-31837",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 489931,
  "published_at": "2026-03-10T21:57:44.387+00:00"
}