{
  "affected": [
    {
      "ranges": [
        {
          "events": [
            {
              "introduced": "1d658336b05f8697d6445834f8867f8ad5e4f735"
            },
            {
              "fixed": "f615b884310bf82d0014e3b5a92eb9aa88146685"
            },
            {
              "fixed": "7a1d0501cbb962beba23377035d667bf3c1726ee"
            },
            {
              "fixed": "9d94f046b23de0f77849ea69133063c949297e30"
            },
            {
              "fixed": "2e4ce62385c1b8a887c5370af058ac7b52a8eaf9"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Linux",
        "name": "Kernel"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "3.10.0"
            },
            {
              "fixed": "6.12.109"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.13.0"
            },
            {
              "fixed": "6.18.50"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.19.0"
            },
            {
              "fixed": "7.2.4"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "database_specific": {
    "cna_assigner": "Linux",
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/89xxx/CVE-2026-89539.json"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nSUNRPC: reject duplicate CREDS_VALUE options\n\ngssx_dec_option_array() walks the wire-supplied option array and, for\nevery entry whose name matches CREDS_VALUE, calls\ngssx_dec_linux_creds() on the same struct svc_cred. That helper\nunconditionally installs a fresh groups_alloc() result into\ncreds-\u003ecr_group_info without releasing whatever pointer was already\nthere:\n\n    for (i = 0; i \u003c count; i++) {\n        ... decode name ...\n        if (length == sizeof(CREDS_VALUE) \u0026\u0026\n            memcmp(p, CREDS_VALUE, sizeof(CREDS_VALUE)) == 0) {\n            err = gssx_dec_linux_creds(xdr, creds);\n            ...\n        }\n    }\n\nA reply that carries two CREDS_VALUE entries therefore overwrites\ncr_group_info on the second iteration and orphans the group_info\nallocated by the first call. The earlier free_creds path only\nreleases the last cr_group_info via free_svc_cred(), so the first\nallocation's refcount stays at one and its kvmalloc-backed storage\nis leaked. No in-tree caller of gssp_accept_sec_context_upcall()\nexpects more than one CREDS_VALUE per reply.\n\nFix by tracking whether a CREDS_VALUE option has already been\ndecoded and returning -EINVAL on any subsequent match, so the\nfree_creds path releases the single group_info that was installed.",
  "id": "CVE-2026-89539",
  "modified": "2026-09-13T03:30:43.113113532Z",
  "published": "2026-09-11T19:44:16.699Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/2e4ce62385c1b8a887c5370af058ac7b52a8eaf9"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/7a1d0501cbb962beba23377035d667bf3c1726ee"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/9d94f046b23de0f77849ea69133063c949297e30"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/f615b884310bf82d0014e3b5a92eb9aa88146685"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/89xxx/CVE-2026-89539.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-89539"
    },
    {
      "type": "PACKAGE",
      "url": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"
    }
  ],
  "schema_version": "1.9.0",
  "summary": "SUNRPC: reject duplicate CREDS_VALUE options"
}